i found a way to package roblox in .zip i have to much experience for this to not be possible
a ZIP file would still mean some1 will have to install the robolox player.
i think your best option here is to upload the robolox game to some kind of a cloud based platform, search google i dont know if i'm allowed to write it in here :)
Technically you're not allowed to package the Roblox Player in your zip package. Itch would probably take it down.