Zarokh death without missing mechanic

After completing the sands of time mechanic and continuing the boss fight I was suddenly killed as if I had not completed the mechanic in time. The trigger for a second mechanic also appeared as I died even though it was only a few seconds since I had finished the first one. Thought is that the timer continued despite completing the mechanic.

https://www.reddit.com/media?url=https%3A%2F%2Fi.redd.it%2Fddqfmwtnooae1.png

Been a bit since the first post, but I had the exact same thing happen to me. He started the phase after the hourglass mechanic then almost immediately went back to it and I instantly died. It was not the same animation as when you fail the hourglass. Time paused, he appeared on top of me and I was instantly dead.

The death message was the one you get for killing your self due to self damage, which is not possible for my character.