possible damage numbers bug in elder guardian arenas with destructive play

There is a possible bug I have encountered twice in Settlers where my character suddenly becomes much less tanky while fighting elder guardians with the Destructive Play atlas passive.

character stats:
Juggernaut
Brass Dome - full crit immunity
88 lightning resist
purity of elements - shock immune
7 endurance charges + unrelenting - 35% elemental damage reduction
4500 life

I have done the Eradicator fight with similar tankiness dozens of times last league and at least one other time in Settlers (including a Maven: the Twisted invite in settlers which was as easy as usual) and was able to completely facetank the cloud lightning bolts, barely even noticing the damage; all of a sudden in this one map it oneshots me. I calculated the hit damage would have to be about 57k - 58k in order to do this (4500 life and taking 65% of 12% of lightning damage), which is about 6 times the total cloud bolts phase damage as listed in poedb. The other bosses added by the maven were also doing multiple times the damage they usually feel like they do.

A similar thing happened in a Constrictor map, also with destructive play. I think I was killed by the boss of Lair map whose damage is almost never even noticeable.

This has caused me to at least temporarily quit PoE out of frustration because it feels like the juggernaut is unplayably squishy but I would like to know if it was all just because of a newly introduced bug that procs only some of the time.
thanks

And this was on a normal map that had no map mods? Reduced max res scaled with atlas tree could easily explain this.

I'm still under the tinfoil theory that lightning damage does extra damage this league. But map mods could also explain your deaths.

I never run -max res because it bricks RF; I think there was like a 30% increased monster damage or 30% increased boss damage mod (not both) but that doesnt account for apparent 600% increased damage [cloud bolts total to about 10k according to poedb, I should be able to easily tank 13 or even 16k hits]