So about starting at 6:10, right during the server crash. I decided to play legendary campaign with my friend. And when we started the first mission. We were both Master chief. And blah blah, we started mission 2, and thats when it got worse, we both were locke, and there was a bot with NO ai. It just stood there.
And the game did not allow me to select a character. Plus all 3 other members of the team were there, (both of us could command them).
I hypothesized that when he selected canpaign he accidently clicked solo and it bugged out, or coop broke. When he put us into a lobby, it told me connection lost but i remained in.
Take a look at a bit of this madness, its quite funny.