Do your homework about the squad you are trying out for. Does it say they require tumbling? Do they compete? Are there multiple squads?
The answers to these questions might help you in your decision. While tumbling will always factor in as a plus in tryouts, if your college doesn't require it or compete, then it may be a smaller factor than other universities tryout scores. You can always contact the coach as well to see what he/she would recommend.

Good Luck!