Also as I chose the name number as him so I would have been chosen if I was in the time limit.
No you wouldn't.
What I do is that
I go down a list of people that choose to be in.
Lets say #1 on the list chose 15
I roll and it's a 10. Since it's not 15, I go to the next person and roll again to try and get their number. And so on.
Also if you spam you're not in.