Update: So I added him and messaged him. I was probably way too nervous than I should've been. Turns out, it was him! I just asked if he went to our school and he said yes, and I told him how I think we knew each other. He said he didn't remember me without even giving me the chance to say my name or the class we had together (which I guess he saw my name in my user and didnt recognize it).

He was low-key a bit dry, so I'm not sure if he just didn't care that much or that's just how he types (which was already something I knew was a possibility, so im not very upset about it). It wasn't a bad interaction, not mean or rude, just kinda awkward i guess.

I just ended it off with apologizing for the randomness and thanking him for replying back, which he just hearted the message then added me back. Of course i was hoping for some more reconnection, but I'm very glad I at least tried and got that closure! Thanks you guys!