It should be impossible for you to see the items if you delete the folder they're found in, you could also look at the steam folder if that doesn't work.

The way that some people have been fixing this issue is deleting the workshop folder in your %appdata% heat signature file

I think it's based on just when they get around to it. I've been waiting for a little under two weeks. Hopefully both of the games we've requested get accepted.

https://www.speedrun.com/requestgame