I think that Manfred wanted to show Frederic that all was normal at the castle, and that he shouldn't believe a mere domestic (I like this name for a servant ;-)

So they go off to dinner.

He would like everyone to question, like Manfred, 'Are my own domestics suborned to spread tales injurious to my honour?'
The tale about the giant arm and foot, spread by the domestics Diego and Jaquez were proved false by none other than the Friar and Hippolita.

I wonder if these parts appeared only now and then.