Originally Posted by Thorvan
Sounds to me like you might have gotten lucky with fly the co-op
That didn't happen for me. I can also confirm that the Petrovic trophy didn't unlock across multiple sessions for me. I previously had the "Taking it for the team" trophy, however 'Auf Wiedersehen Petrovic' did not unlock until I had re-completed all the team matches during the same session.
Do let us know if you are more fortunate though. Perhaps Rockstar are able to do some wizardry server side and may be sorting things out. Or as I said earlier, perhaps you're just lucky!
See Edit to original post