Help! Last Boss Remains (Divinity: Original Sin)

good people, help - for some reason the portal to the final boss (at the End of Times) does not work. Everything is done, everyone is ready, NPCs wish good luck in the battle with him, and the port is not working (although it is on and lit). Most likely the bug is the game, tk. we play over the network - can someone on our save go to the portal, save and throw the save back?)
https://yadi.sk/d/vXT3mAmpudBZ6

PS Somewhere on the Internet I saw a complete list of magic castles in the game (those that open only with a magic pick), there seemed to be about 8 of them for the whole game - can you tell me the list?