Can a husband be with two wives in one room or one bed?

It is not permitted; scholars forbid a husband from gathering his wives in one bed or having relations with one wife in front of another.
This goes against propriety and modesty (haya'), exposes one's ʿawrah and private matters to others, and hurts the wives' feelings. It also denies each wife her right to her turn and her privacy. Even if the wives agree, many scholars still rule it haram or strongly disliked because it involves exposing the ʿawrah and indecency. Islam teaches that every intimate relationship between husband and wife be conducted privately and with dignity. See Fiqh of polygyny.