Many suggestions have been made on how you determine who hit withdraw, no suggestions have been made for alterations to this system that would not invite more abuse.
Nothing currently in the game is sufficient to determine who can cause a queue to fail, because all we get is "your registration is withdrawn". Sure, if someone is just afk you might root them out with a ready check, but not if someone is deliberately trolling the group. We *were* talking about dealing with trolls in this topic, right?

Along with the change of only the perpetrator getting the strike, the only change to the system needed is for the message to instead say "soandso's entry could not be confirmed. your registration is withdrawn." What is so complicated about this, exactly?

Also, this system is inferior to what, exactly? Certainly not inferior to the previous status quo.
It's inferior to what it easily could have been. It left behind a major flaw that wasn't there before. Fixing something and leaving behind other very obvious problems doesn't merit my praise.