I bet that most of the guild already has it.  You would only have to do it for the people who are actively chasing the title, and you can verify who has it by inspecting their profiles.  If everyone is used to doing it at a specific time (e.g. 8pm), you could have the officers manually launch the raid at 7:57 instead.  That way the player with a head start could tap the raid first, then everyone else runs in at 8pm.  
We did something similar in my guild to help a member out with the Jedi Knight Prestigious Quests - he needed top ranking in HAAT, so we gave him a head start.  
Since this isn't a bug, the best place to propose your ideas is in the Feedback Home in the forums:
https://forums.galaxy-of-heroes.starwars.ea.com/categories/feedback-homeGood luck!