My soldiers all have the Psi armor equipped...
Hm. Interesting. I loaded up the game this morning, after turning off the box last night, and it allowed me to use the Gollop chamber. So I finished off the game. I used the impossible/ironman save that was uploaded, but after killing the final ethereal, the ending sequence played like usual, but then the game gave me the defeat screen.
Anyone else have this happen? Anyone who was able to finish and get the success willing to upload their final save?