It’s close to midnight here now and I’m just about to fall asleep, so I’m not looking at the code right now, but see if there is a possibility that the printinitial function is called before the register function is done.

jquery is Async, so that might be it. Use the wait() operation in the backend or done() function on the client side if you can to make sure the printinitial function is not called prematurely.

I can't reproduce that specific problem. And I don't know which changes you've made to your code now.
But as long as I open two browsers and have two players, the code is working on my end.
(However, if I just have one player some problems occur, but that might be something you're thinking about handling down the road?)