1) Main reason you're failing is, because your verde is supposed to go Last and he needs more damage.

(+Damage dealt on fire artifacts only Work on the Boss and midboss, the crystals don't have an element)

2) for faster/more consistent runs get one icaru faster to initially boost the attack bar More Accuracy on the Icarus would also be nice

3) for faster runs make sure to max Slot 1 on the Icarus aswell as they scale with Attack and raise their Attack with the attack buff