If you are in position and facing me, I am not going to look at your eyes to make eye contact before I serve. I'll take note of where you are and where your partner is but then I'm looking up at the ball. If you want me to wait then put a hand up so that I know it.
I don't think you have much of an argument to have the person serve again if you are in position and don't put your hand up to signal that you aren't ready.
Granted, I am not a quick server so maybe the protocol is different for people who push the line a bit. But I don't think that I have ever waited for eye contact before serving the ball.