Think fast, Tozier. At least he wasn't currently drilling, which would surely answer the question of 'what the everloving fuck is going on in here?' so that was a bonus. Ava reacted with surprise, blinking out of existence (though she was still there, he knew - probably waiting to bludgeon this poor guy if necessary but it wasn't going to be necessary) and Richie just...turned on the human stupidity act. Not difficult.
He was a comedian, not an actor, so he'd see how it went. "Oh, shit, sorry - " he apologized, inching toward the door and past the room's occupant. "Canadian weed is intense. I thought this was where the feng shui workshop was." Nevermind the lady in the suit, nothing to see here.
Ava could hopefully just phase herself past the wall and Richie, well - he made a grab for the doorknob and bolted out. Enjoy that new feng shui without them, friend.