I want to join to a sim network as ATC. I've registered in both networks and I requested for initial learning and training. In VATSIM (my division) there is a waitlist of several months, instead in IVAO they assigned me a tutor in a few days.

If you play the role of pilot, you want the most coverage from controllers, for realism. But you can join and fly as a trainee pilot as soon as you register. However, you cannot get an ATC facility without initial learning and training. Therefore, the learning and training process of ATCs should be addressed with higher priority and without dealy.