Hello, I am a game developer on Roblox and I would really like to join the game jam. The only problem is itch.io only seems to allow download submissions, and I have no way to do that due to the nature of Roblox games. It would have to be a link to my game on the Roblox website. Is there a way for me to still submit my game? Thanks.

you could always add an empty text folder to your games download and just tell people not to download it and if the jam allows it maybe hide the download and then you just add the link to your Roblox game

But, maybe you can upload the .rbx file and upload that as your game, so when people open the file, it will redirect them to the Roblox website or app. This seemed to work for me on the itch.io app and website, so you can go ahead and give that a try.