Can't target Ziggurat nightmare boss Catarina

I killed her minions and she became invincible. However, she kept being invincible for too long (10 mins+), I tried to TP back to hideout, died and returned but she's still not targetable.

I can't post the video in the forum so please see this reddit post https://www.reddit.com/r/pathofexile/comments/1stzpx6/is_this_a_bug_ziggurat_nightmare_boss_catarina/

The post was removed. I uploaded to youtube
https://youtu.be/ZizYEDuBSYg