Aargh. I hate unprofessional behavior - even in school. And 95% of what's going on with your play is the director's fault. It's their responsibility to set the rules (e.g., contract) and follow through or cancel the play.
If you really want the play to succeed, might want to work out some what if situations and try to figure out solutions. For example, what if the jocks don't know their lines by the time the play starts? What if folks forget blocking? And so on.
If you can think of constructive ways to help the situation, offer some suggestions to the director. If they're not willing to deal with reality, figure out how you are going to handle yourself if the play actually goes on. Rather than offer good luck, guess it should be "break a leg".