I have found that if you go to another character, then change characters while playing as them, it will load you in. But you should exit that area to keep it from freezing while you're in there.
My cousin and I made it to Vellosk yesterday. We got back on today after quitting as soon as we got there, and are stuck at loading Vellosk screen. But it will allow us to get in the game if we create another character. Please help.