Keeping in mind that it’s a work event, even if informal:
Thai:
Sai Tong – nice atmosphere on both levels, good food, they won’t rush you (Cha Long has good food but is more expensive relative to portion size and they will rush you, Lum Lum is also good food of a different sub-type but is small so they will also rush you).
Or try Cambodian at Bayon.
Korean:
I’ve had many fun k-bbq work dinners over the years. Miss Korea or Don’s Bogam are reliable, Samwoojung is quieter. Or Hometown hot pot & bbq could be a good crossover option since you’re planning to do hotpot anyway. Away from bbq, Odre feels high end at a bargain price.
Tapas:
Boqueria and Soccarat both have good happy hours with food that transition easily into dinner. Alta is old school but always good.
Red sauce Italian:
A classic and delicious nyc experience made for family-style eating. Carmine’s is a whole thing (uws less of a zoo than times sq) 
. Or go somewhere smaller, no shortage of options. But a bit of a zoo can be fun.
