"It was greatly my wish that he should do so," he added, "as soon as his marriage was fixed on. And I think you will agree with me, in considering a removal from that corps as highly advisable, both on his account and my niece's. It is Mr. Wickham's intention to go into the regulars; and among his former friends there are still some who are able and willing to assist him in the army. He has the promise of an ensigncy in General -- 's regiment, now quartered in the north. (Chapter 50)

In Chapter 50 Mr. Gardiner writes to Mr. Bennet with further news. Mr. Gardiner speaks of “former friends” still willing to help Wickham in the army. I have always read this to mean former friends in the militia from which he recently absconded but on this read I have questioned it. Who are these former friends willing to help him? They can only be drawn from two sources, friends before Wickham joined the militia or friends acquired after.

Candidates in the militia for former friends are Col Forster, Denny, Pratt and Chamberlayne. Pratt is one of the men temporarily fooled by Chamberlayne dressed as a woman in Chapter 39. The only other time he is mentioned in the text so far is in Lydia’s letter to Harriet in Chapter 47 in which she asks her to apologize to him for not keeping her engagement to dance that evening. Chamberlayne is only mentioned the one time in Chapter 39—perhaps that is enough to get a feeling for his character. Since Pratt and Chamberlayne are barely mentioned in the text I think only Col Forster and Mr. Denny of the militia are in the running for former friends which might help Wickham.

I grieve to find, however, that Colonel F. is not disposed to depend upon their marriage; he shook his head when I expressed my hopes, and said he feared W. was not a man to be trusted. (Chapter 46)

Col Forster has had a great deal of trouble and embarrassment on account of Wickham. Wickham left his post; he eloped with a foolish young girl in the colonel’s charge and as bad as eloping is, a marriage never takes place. He tracks the pair, making every possible enquiry on the road without much success before heading to Longbourn and finally must settle up Wickham’s debts in Brighton, reimbursement aside, it is still IMO an annoyance and possibly even an embarrassment to clean up after one of your officers. When the colonel visits Longbourn he did not speak so well of Wickham as he formerly had and said Wickham was not a man to be trusted. I think the only reason that Col Forster might help Wickham would be because he felt partly responsible for Lydia and if helping Wickham’s career helped her then he might do it.

She had never heard of him before his entrance into the -- -- shire Militia, in which he had engaged at the persuasion of the young man who, on meeting him accidentally in town, had there renewed a slight acquaintance. Of his former way of life nothing had been known in Hertfordshire but what he told himself. (Chapter 36)

Denny persuaded Wickham to join the militia and his unwillingness to repeat his accusation that Wickham never intended to marry Lydia when questioned by Col Forster still shows some loyalty to his friend IMO. Denny may have renewed a slight acquaintance with Wickham in Chapter 15 but by the time of the Netherfield ball in Chapter 18 it is much more intimate. He knows of Wickham’s grievance against Darcy and tells Lizzy:

Wickham had been obliged to go to town on business the day before, and was not yet returned; adding, with a significant smile -- "I do not imagine his business would have called him away just now, if he had not wished to avoid a certain gentleman here." (Chapter 18)

This is information that Wickham has not made public as Darcy is still in the country. Denny renews his acquaintance with Wickham, his knowledge of Wickham’s grievance against Darcy and his refusal to repeat his claim Wickham would not marry Lydia is highly suggestive to me that Denny is still a friend to Wickham. He might still be willing to help Wickham but how much influence or connections he might have is a mystery.

Mr. Gardiner did not write again till he had received an answer from Colonel Forster; and then he had nothing of a pleasant nature to send. It was not known that Wickham had a single relation with whom he kept up any connexion, and it was certain that he had no near one living. His former acquaintance had been numerous; but since he had been in the militia, it did not appear that he was on terms of particular friendship with any of them. There was no one, therefore, who could be pointed out as likely to give any news of him. (Chapter 48)

Former friends before Wickham joined the militia would include acquaintance from school and Cambridge and those after the death of Mr. Darcy when he pretended to study law. Of his numerous (I assume) reputable acquaintance Mr. Gardiner can find none who have kept terms of particular friendship—did they learn his true character the hard way? I do not suppose we can say with perfect clarity but it is obvious his pleasing manners did not encourage many to stay close. Individuals mentioned in text from his life before the militia are Mrs. Reynolds in Chapter 43, Mr. Darcy in Chapter 16, Darcy chapter 15, Col Fitzwilliam in Chapter 41, the ladies at Rosings Chapter 16, Mrs. Younge in Chapter 35 and Denny in Chapter 15.

The Rosings ladies can be eliminated because Wickham probably never had a relationship with them and also Mrs. Reynolds, who by situation and inclination is ill equipped to help Wickham in any way. Mrs. Younge is obviously disreputable due to her involvement in Wickham’s seduction and elopement plans with Georgiana but while partial to Wickham she could be bribed by Darcy to betray him as told by Aunt Gardiner in Chapter 52. Mrs. Younge cannot be someone who could help Wickham to a commission in the army however. Darcy and Col Fitzwilliam could be considered “former friends.” Darcy according to Aunt Gardiner, took everything on himself. He must provide the funds to pay off Wickham’s debts and for his commission but is Darcy the one who talked him into joining the regulars? Some negotiation went on between Darcy and Wickham because Aunt Gardiner says:

"They met several times, for there was much to be discussed. Wickham, of course, wanted more than he could get, but at length was reduced to be reasonable.” (Chapter 52)

Is Aunt Gardiner only speaking of money or of how to set Wickham up in some profession or perhaps both? I can easily envision Wickham plying Darcy for the Krypton living or some equivalent fortune so he could just live off the land or interest. Col Fitzwilliam would also be considered a former friend but so far there is no clue that Col Fitzwilliam is involved in helping Wickham to a commission in the army. It is not farfetched however, with an earl for a father and his army connections that he could have some influence in getting a commission even for a worthless cad like Wickham. The colonel is certainly trustworthy but would Darcy have brought him into this business when he must wish to keep knowledge limited to as few persons as possible?