I have reported this problem already to the "bug-fix" section. But I don't know how CG collects "Known Issues", so I will post this here.
As the picture above have displayed, when using Sith Eternal Emperor (SEE) against Jedi Master Kenobi (JMK) teams, my SEE with 3 stacks of Beskar Armor (which prevents being critically hit) is SOMETIMES critically hit by General Skywalker (GAS) under JMK lead. This happens EVEN when I linked GAS and any other enemy with my SEE.
Here's another picture of a different battle that may serve as a proof.
Vulnerable:Will be critically hit if able.
3-stacks of Beskar prevents crically hits. Vulnerable only applies to units without Crit-Immunity or status effects that prevent critical hits.
[EDIT] Telekinesis: Deal Physical damage to target enemy. If possible, this attack will critically hit enemies with Armor Shred. If the target enemy is Dazed, reduce General Skywalker's ability cooldowns by 1.
1. I have photos of GAS not critically hitting SEE with Armorer shred.
And GAS's Force Grip says "If possible, this attack will critically hit enemies with Armorer Shred". Not always.
2. Says the game. Says the community.
It is mentioned in the reddit post comment. And if you check the status effect mechanism on Swgoh.gg, you can see that it indeed works like this:
GAS Telekinesis/Force Grip with Armor shred: Modify stat Physical Critical Percent Additive by 500000% (additive)
Vulnerable: Modify stat Physical Critical Negate Percent Additive by -500000% (additive)
Bescar Armor L3: Modify stat Physical Critical Negate Percent Additive by 999900% (additive)
(500000%)*2 - 999900% = 100%
There is no true immunity in this game. Everything has a percentage value.
Okay, that makes more sense. Thank you! I guess it is still just "designed as intended" haha