Can I save a Creme Brûlée with a soggy crust?
Just before the party, sprinkle some granulated sugar on top. Use a blowtorch (preferred) or a very hot broiler to "brulee" the new sugar. That will cause both the old and new sugar to get browned and crunchy.

I just saw this on a related question. Alton Brown on Creme Brulee. He shows great blowtorch technique, do it just like that and you'll be fine, no need to remove the soggy layer.