Max told E! Onlinethat Glee currently has no plans for Karofsky to return. "I certainly hope [Dave returns], but I don't know," Max said. "I have not been told, so [Tuesday's episode] could wrap it up." What? No! There's still so many ways Glee could continue to explore the character. This can't be his last episode!
Max added to Entertainment Weekly, "It’s kind of open-ended. As an actor, I would love the opportunity. As the character, we shall find out."
On top of that, TV Linereported on February 28 that Max has booked a new TV pilot called Last Resort. So while this new role certainly won't make it impossible for him to return, it will make things more difficult. Filming for Last Resort takes place in Hawaii. That would make quite a commute back to LA for Glee! That said, the showhasn't been picked up for a full season yet. Plus, Max's character isn't guarenteed to be a series regular. He's still listed as a guest star.
So while we're hopeful for Karofsky's return... we don't exactly have the definitive answer we would like.