1996 Pontiac Grand Prix no 1st or reverse

My son put his 96 pontiac grand prix gtp, into a snow bank and after trying to rock it back and forth to get out he was pulled out by a friend with a bronco. After being pulled out the car when put into drive will not move forward or go in reverse. When I got there I flipped a little swith on the dash to second gear start and the car drives forward in D,3,2 but does not drive in 1 or reverse. I know he probably fried 1st and reverse, but is there anything I should check before proceeding with a major repair.

thanks Jon C