For a jam that so heavily protests that it is aimed towards beginning developers, this one was certainly not geared towards it compared to the many others on itch.io
Making entrants fill out a third party form through a link just to participate is incredibly dubious and inappropriate, serving zero purpose beyond using people to harvest information. Virtually every other jam on itch.io does not do this, there is no excuse for yours to. Requiring entrants to give you their email address as well breaches into an entire new level of impropriety. Neither of these things are a part of the itch.io jam system because they are both completely unnecessary, serving only as an underhanded means of benefit for the hosts.
But much more significantly, arbitrarily threatening entrants that they will be "reported" if they dare to enter their game into multiple jams is ridiculous. Entering multiple jams that your game is eligible for, which is often the scenario with how many are hosted on itch.io at the same time, is an extremely basic means for which a developer increases their exposure. So much for having any interest in supporting developers in any way, when you threaten them not to give their game more exposure. Completely absurd.
Regardless, this jam has ended and because it has ended we will be entering our game into another applicable jam that it is eligible for. We hope that you learn from this and strive to make any future jams you host significantly more developer friendly, by simply not imposing inappropriate demands and limitations on participants. As this entire process is after all, about the benefit of developers.
Have a good day.