That is correct, but then you have to handle the Wade, Lena and Holly situation as well, which can be a pain. Here much depends on the general situation at the start of the holiday, who likes whom, who has a stressed relationship, who has broken up, etc. It is possible to gain a roommate after the breakup quite quickly due to this, whom you cannot get rid off for the night.And you can put Emma and Perry in the same room and still make sure that she's not going to return his feelings. Just to maximize enjoyment .
As said, the easiest and foolproof way to get a storm free room is coupling Emma and Perry up.