My macbook pro mid 2012 is randomly restarting

If I twist the case slightly I can get it to reboot most of the time. The Genius Bar guy suggested the bottom cover needs to be replaced because a piece of foam that holds the holds the ram stable gets compressed and lets it shift causing the restarts. The ram idea makes sense because I did get some 3 beep events after the freeze. He reseated the ram and it was mostly OK for a day but then it froze and would not restart with the three beep code until I slightly twisted the case then it started. Does the cover suggestion sound reasonable? I am under Applecare until July but this my daughter' s machine at college so being without it is really bad.