I am following the strategies I've seen online (I'm a SCH by the way), kill healer first, then the Centurion (magitek), the next wave pops before I am able to finish killing the Centurion, but it's almost dead so I'm able to finish it off, and then I kill the Claws, and then the Aquilifer who heals the Colossus, and then the guides say to kill the Colossus, but by now only one of my NPCs is left alive and he is almost dead and I fail the duty since he dies...

I am pretty stuck on this as healing NPCs in this duty is pretty pointless just because of how many NPCs and enemies are involved with the duty, plus all of the AEO and the need to kill certain mobs. I don't even have time to kill other mobs in waves besides the ones that the guides tell me to before the next wave pops even though the guides say to try and kill some of them. Should I have my healer fairy summoned for this duty? I don't think even if I do it actually heals the other NPCs so that feels like it'd be pointless... Could use some help on this, thanks!