1. reverse and 5th are on the same assembly(rear of the trans) they share the same shift rail and fork. so see if you can shift into 5th.
2.a new clutch wouldn't cause this unless it had something to do with re-assembly.
3.i haven't seen reverse blow a hole into the case. so you need to look and see where the fluid is coming from. and remember reverse is near where the t-case bolts up, not the bell housing.
4. dont drive and dont crank the engine, the more you use it the more it will cost to fix.
if i had to guess the issue with 5th is inside, but shouldn't cause a leak, so need to find the leak area