I might have created a new card sleight, but I'm not sure. What should I do? Submit a video on the marketplace.
No.
The market place is for well polished, tried and tested moves, sleights, tricks, routines, or principals.
You need to practice it, then perform with it, and see where and how it works. Then build on it. Only then should you release it.
As for the move, it is possible (and probably likely) that you didn't invent it, but you rather re-invented a move that already exists. Check on Conjuring Archive.
If you want to describe the move without doing it openly on the forums, PM me. If I don't know (and I probably wont if it is more advanced), there are a couple other people I would direct you to.