Possible explanations: Waitlistees/applicants in general are sorta like privacy patients...your name may come up, but it's against institutional policy to say anything.
Or there might be a computer program that the friend of your friend doesn't have access to.
My advice? Put all dangerous objects away, get drunk, and go to bed. Call the office in the morning. However, considering the situation, do you want the med school to know that you've been sluething? Exactly how would the conversation go?
"um, I'm a waitlistee, and I have a friend who is a friend of Dr. Soandso, and Dr. Soandso told my friend who told me that he looked up my name on the computer and there's no record of me, so I'm really worried about my status..."
I hope there's some logical explanation for all of this. I don't certainly don't envy you, as I'm waiting until May1 before I find out where I am on a waitlist. Anyway, lots of HUGS!