As a mission table lover (unpopular liking) this is a mess... What if, rather than cancelling all missions, only croman and meatball associated quest cancel? As those are the unique followers common to all covenants, it seems legit to think they abandon whatever mission they are doing to follow you around. That would solve the problem and will not kill mission tables on mains that also want to farm other covenant rewards, transmogs, or even experiment with their new abilities. Please let me know how I could reach the dev team to suggest this solution, as it seems a rather easy concept (not sure how difficult it could be to implement).