So does jigu know mc is from the game or not?

Jigu doesn't know! ^^

So why is he acting like that? Is he just that much of a tsundere?

rather than knowing, i would say he is already suspecting all those coincidences which is why he is avoiding him on game and not answering his texts.

He doess now, thats why he ignoring lmao

My memory's a little hazy about the story, but I think at this point.... Jigu knows. But he def thinks mc is a creep/stalker