King Daniel Into Darkness wrote:
STVI makes it pretty clear the crew have been broken up for at least 3 years (McCoy didn't even know Sulu was a Captain - and the film opens with him returning from a 3-year mission!) and are reuniting for the peace mission.
I think you're reading too much into McCoy's statement. He probably said that because it would seem only natural that if every other Enterprise
crew member were summoned to a meeting that Sulu should be there, too. It's possible that Sulu may have collaborated with Kirk and the Enterprise
on assignments after taking command of Excelsior
. These assignments wouldn't necessarily interfere with his mission in the Beta Quadrant. Perhaps McCoy assumed his crew would be coming along for the ride because it happened before.