It wasn't that Amycus was ignoring Dominic's question, he just didn't feel like explaining himself where their housemates could hear. He poured the drinks and passed one to Avery before sitting down on the edge of Rabastan's bed since Dominic was on his.
"As for what happened, I got into a fight with Rodolphus" he said, taking a sip from his glass. He flicked his wand to open the window asking, "Pass me that ashtray?" Opening the window before he smoked was a habit from living with Rabastan and even though he wasn't in the room with them it just seemed like the right thing to do.