Update: Reinstalling the game, resetting the wifi router, and connecting using a LAN cable were all not able to solve the problem and I still get the "Joining failed: Connection failed" error. Really hoping anyone knows a workaround of some kind I haven't thought of. Was able to connect to online multiplayer in another game no problem and streaming services all work as well, so the internet seems to be working in general on the PS5. My friends are still able to connect to each others' multiplayer lobbies with no issues, it is just if I try to join or if they try to join one that I create.

I have uploaded a brief video what it looks like when I try to join a multiplayer lobby on the imgur link below if that helps at all!
https://imgur.com/a/biY84n6

Thank you all again and I am hoping this can get fixed soon because we're loving the game in general!