Redshift Community

I have a problem, my last quest is impossible(?) to solve... I have already been to the other Dimension to wipe out the Savirs, and got the quest to pacify the spirit of Gleb's brother after that. But I can't get back into the Dimension, because the soldier closes the portal after finishing the kill the Savir soldiers in the other dimension quest. If I ask him to get me into the dimension again, he says he can't because of the magic sponge which is in the treasury, right? How do I get in there, and is it still possible to finish this quest. Please answer... Please

Try with personality greater than 45. But if you killed the Duke of Poltergeists, you can't go back.