UPDATE:
I figured out that no matter what link you try, it will still give you the same error.
The error has nothing to do with the link.
Also, the same issue is still occurring to me.
Bad news, I wasn’t able to contact bug support, as well as getting temporally kicked out.
Ill just try using a different account then to upload the YouTube video.
I was able to upload the YT video on the game page with my other account! I have no clue if its normal or not, but it weirdly says the content is blocked. Also, if this doesn’t work, DON’T USE YOUR ALT to upload the video. You’ll just lose 500 Robux.
I think this issue is account based, so you have to somehow transfer Robux to another account. I might say more to this later.