I guess that I should add that the raid boss was the level 80 version from the 20 tag summon and it ko'ed 3 of the units in the squad. I was still getting about 2.5 mill damage from that squad so the main problem is that the other members were still a bit squishy. Once I finish adding some attack amphies to my units and upgrade their equipment I should be able to deal more damage.
Still, it is interesting that there's a turn limit programmed into the raid boss fights. Once most certainly needs to build a good balance between offence and defence on their squads if they want to do some serious damage to the super bosses.