Oswald showed up along with Sully, looking pretty dapper (although obv. his clothes were not as expensive as these). He brought a fancy bottle of wine as a gift for the hosts, and was (GASP) completely sober and on his best behaviour. He avoided Regina and Theodore (and everyone else who is probably mad at him) as much as he could, which probably resulted in his spending most of the night hanging out with Cee and the salukis. He drank a little so as not to appear stuck-up, but overall, he stayed classy and may not have talked much, ESPECIALLY not about anything controversial.
Needless to say, his pop did not make an appearance.