The room is mainly for them to change their outfit or rest. It depends if yours is dinner or lunch ba.
If it's dinner, usually there is abt 2-3 hours break time where they can rest. So it will be good to have a room for them to rest and wash up. Probably they might head home first before the dinner banquet.
If it's lunch, it will be quite packed and might not have enough to rest. Depends if you have Soleminzation, gate crash and tea ceremony back to back.
If it's a resturant, probably can ask if there is a private dining area for them to rest. Cause you probably book the whole resturant already. So they can give you complimentary room.
Hope this helps
