Fight arena issues - Zalmarath, the Colossus

Bug report ID if its needed:
1989783356

Area: The Titan Grotto
Fight Arena with Zalmaranth

Summary:
It is possible to glitch out of the arena during the fight.
An easily reproducible way to do this is to use something like Toxic Growth or Escape shot, that has a backwards moving animation.

Expected behavior:
Not being able to leave the arena and get "under" the Zalmaranth

Observed behavior:
Easily repeatable - accidental.
Causes game to lag hard, and relocate the character back into the arena.
Very disruptive to the fight and not a fun experience.

I assume this happens with many animations that move the character.

I had this same issue while fighting the Colossus.

I'm playing the Ranger.

I would try to use Escape Shot, but the game would throw me outside/under the map.
When it finished lagging & glitching, I was back on the map, but ended up dead a few times before I figured out that I couldn't use that skill anymore.

Another issue I had during this battle was that my Fulminating Concoction skill would be thrown down next to me instead of going toward the Colossus.

My lightning arrow shots would also sometimes shoot to the left or right instead of where my cursor was pointing, which was directly at the Colossus.