Your game is part of Game Jam Plus, fear not!
Although yeah, you missed the registration for the itch io jam.
Theoretically you should have sumbitted the game in the jam's itch io page, but as itch was having issues by then, it was also valid to send it on google drive for instance.
As many people had lost the first opportunity to do so, they reopened for submissions for a week that ended yesterday.
So let's hope they reopen it again so you can submit it too! But keep in mind you are still elligible for prizes and all stuff!