I've never sponsored a game jam before so I don't really know how it works.
My idea for sponsoring might be a bit different - it would scale with the amount of submissions so payouts might be a bit smaller at first. But it would allow me to sponsor many game jams, frequently. I run a small business and would love to contribute to the gaming community.
If anyone is hosting a game jam and is looking for a sponsor, feel free to reach out.