I've been watching this thread for a while because I'm having the same annoying issue on XB1, my brother and I would love to play coop. But I want to make this post now because the unrealistic attitude of some people here is even more annoying to me. Please stop raging at Raze, as he said the ball is in Microsoft's park right now and he's not a spokesperson for them.
Larian's actions and communications regarding the patching process has so far been above average in my experience. I'm hoping that Microsoft takes its time to properly test the patch in a production-like test environment. Also, while I hope this patch fixes the issue ASAP, be prepared for a possible longer wait in case the fix does not work. There are no guarantees at this point, only hopeful estimates.