They are able to accept angbaos at ROM.
Among my group of friends, the market rate seems to be around 68 to 88.
I feel that although we are not required to give them an angbao, they still spend time and effort to travel to the ROM location and an angbao is the easiest way I can express my thanks.
I prepared 2 angbaos, 188 for good service (which I ended up giving) and 68 should the solemnizer not perform up to my liking. I was really happy to give the 188 angbao as she was really accommodating and cheerful during our meet ups and on the ROM day.