Freeze immunity bug on side boss in act 2

Found a bug on Kabala, Constrictor Queen boss, as a sorceress.
If you build 99% freeze on her when she throws around grey/white orbs that explode later, it removes freeze build up and she gets immune to it for rest of the fight.
Happened twice, 1st time around 20% life, I died.
On 2nd try it happened again around 50% of her life.
Might be class specific or any other freeze builds.

Update: happened again Tor Gul boss. Freeze build up to 99% then removed and couldn't freeze anymore.