With easy events like this, people will often just go the second that the room fills up, and you won't always even have enough time to even glance at gear/awakening levels because they go that fast. There's no way to even know Maria is awakened at all once the battle begins unless you know her awakened talents and look for them, but even then, you don't know what level she's awakened to or if she has the better rush multiplier or not yet.

At the end of the day, if you're playing as a healer/sharpshooter/defender, you'll be expected to start rushes. Not everyone can know every single character's weapons and rush multipliers. You yourself didn't even mention that Divine Wave Gun will do just as much damage as the earth imbue gun due to the 40% demon killer attached to it.