I requested a ROBLOX game by Scriptbloxian studios and when I checked for it the next day, my game request wasn't there. Does that mean it was rejected or something? I don't think I got notified and if I did, where could I be notified?

Did you request it through the form in the Roblox forums?

If you submitted it through the site, there's a chance that you have certain notifications off so then you didn't get anything telling you what happened or maybe you just didn't submit it by mistake

in the roblox speedrunning discord, we have a channel that notifies what games are currently being reviewed and what games are rejected/added to the website. if you submitted to the roblox submittion forum, it should be rejected/added soon

Can I get a link to the ROBLOX speedrunning discord please?

There’s a button for it here.

https://www.speedrun.com/roblox/forum