Lao Sze Chaun has an upstairs room that might work. They can probably whip up an orange chicken or something like that for your non-adventurous colleagues along with the cold chopped rabbit for the more so. Think I sat up there back around 2003 with Gary, Hammond, Rob and some of the others when the Chowhound departure was announced or close. Good room.
(New) Furama has lots of private space capabilities, and dumplings work for even the milder tummies out there, though more New Chinatown (Bridgeport) than actual Chinatown.
Not sure about Karaoke - is that a thing in Chinatown?
Edit: I see Furama was mentioned in the orignial thread. Maybe not walkable but close to 94!