It's a bit hard for me to tell for sure, especially given that Cudy also changes clothes, but I think the events of the episode all take place during the same day, beginning the morning after House wakes up from his supposed night with Cuddy. He goes to diamond tie!Wilson's office to tell him that he slept with her, and gets a very CTB-like response: "Great! How are you going to screw it up?" The next few scenes with the coffee cup involve striped tie!Wilson. Then diamond tie!Wilson reappears and tells House that if he really wanted to get Cuddy angry, he'd use more serious tactics than poop and pirate strippers.

Anyway, the general point is that we can't really trust any of the events seen from House's POV in this episode, and maybe part of the previous one as well... which would go a long way towards appeasing me re: Wilson's apparent decision to pick House up from the bar and watch him pack for rehab, then completely forget about the whole situation the following day. I mean, he was the only one who knew that House had been hallucinating - surely he would have suspected something after such a surprising announcement?