10 players is a little low, but IMO it should be do-able as long as those 10 players are dedicated tournament players. But if they're missing for vacations, church, etc. then it doesn't sound to me as though they are committed enough. I don't want to be cruel, but if girls and their families are expecting to be able to only practice and play when they feel like it, then they belong on a rec team.
I know you don't want to be the bad guy, but if your DD is putting in 100%, then she deserves to have teammates who are also giving their all.