Re: OOC
Jyn has no clue about Karaoke but she would have shown up because she's definitely using this second chance to experience everything. She also dragged Luke along because of reasons.
Shang-Chi was definitely there. This is his thing and he sang probably more than once. He would have tried to convince Wanda to join him but regardless he would have spent time talking to Wanda and also to everyone else because he's a friendly guy.