A Call to Arms quest broken

[Maenethal]

I've tried dozens of times, but I just can't beat this broken quest. There are tons of issues that prevent any sort of progress, the most glaring of which is that the barathrumites will randomly aggro, even when using only melee, making it impossible to complete the quest. Either "friendly fire" needs a massive nerf/rework, or the barathrumites need to have their AI redone.

There was also an issue with one of the named Templars being immortal (my attacks kept "passing through" as if they were phase shifted)

[Faital Ryuu]

About the second issue you're having, that's a feature that is actually behaving the way they intended. You're talking about the https://cavesofqud.gamepedia.com/Phylactery_squire and the corresponding Wraith Knight. The Wraith Knight will disappear when you kill the squire.

I unfortunately haven't done the quest too many times, so I can't verify particular quirks of the Barathrumite AI. I do remember throwing a grenade and one of the Barathrumites going hostile, but that makes sense. I simply left the zone and went back to reset the aggro. The only thing I can think of with your description is if you're getting hit by Quills, which are notorious friendly-fire. I had a run in Golgotha with some Barathrumite tinkers and I got massacred by all the quills with how little HP I had at the time. But if they're attacking you and you can verify in the combat logs that none of your attacks hit/dealt damage to the presumably friendly Barathrumites, definitely try to delve deeper. Use Debug abilities to quickly reach A Call to Arms to find more specifics on this problem.