The mod applies the bonus damage to any ability by the unit against the "immune" types, not just abilities which use the weapon with the upgrade. That's becuase you assume that the AbilityState passed to GetAttackingDamageModifier() relates the ability which granted the effect, but it doesn't. It's the AbiltyState for the abilitiy being used right now, so the condition is trivially always true. Also, if you would be good enough to set the FriendlyName for the effect so it shows up in the damage breakdown in the shot wings that would be nice ;).