SIMS Medieval: Annexing Yacothia --- how do you give a drink to the soldiers?

I know how to give a drink under normal circumstances. But this one requires me giving it to two soldiers who refuse to leave the Training Yard to go over to the Bard's place to let me serve a drink. I'm in the quest "Death of the Proxy" and it's almost done, just this troublesome step on the way. Very frustrating.