Made a mission, as I have many times before.
When I started the mission in MP my friends spawned as seagulls above their soldier. Myself (the host) was normal.
After two days of trial and error i found that I had used "doStop this" on all my teammate AI so they would not wander around.
I just removed the "doStop this" and now all is fine.
I have used "doStop" many times before. This must be some new error.