Translation:Your aunt was talking about some František.
This translation sounds much more natural: "Your aunt talked about someone named Frantisek." It should be accepted as correct.
I think it actually translates to 'Your aunt was talking about some [person called] František'. The speaker here isn't sure who František is.
I think that all of us native English speakers are trying to figure out what the English translation means. How about: Somehow, your aunt was talking about Frantisek. That seems to be the only way to fit "some how (nějakém)" into the English sentence.