Ok, a summary:
Amari is at risk of being squished by the creature's mouth. Beneath the mouth are dozens, and dozens of tentacle monsters.
Seph is stuck on the side of the beast near it's eyes.
Josstte is riding down one of the creature's tentacles.
Phi is behind the monster.
Three eyes has been destroyed, creating a late hole which an attack could be launched at. You could also attack under the creature's mouth if you can get through the streams of little horrors.
There are many horrors heading towards the Monk, Storm and Jake. I suggest getting the f*ck out of dodge. Long can be ridden, although slowly, if that helps.
Phi, you could quick-hoof it to the monster, or earth jump somewhere?
Like Storm's idea, if someone can make the crystals falls that could work.