I also got this "flame immersion" with Vlaakith. I posted a screenshot of it here.

https://forums.larian.com/ubbthreads.php?ubb=showflat&Main=115632&Number=919705#Post919705

In my case, everything was going on normally, until I had to leave urgently and saved the game during the conversation. Later on when I restarted and loaded up, I had these flames and the rest of the conversation looked as if it had skipped the whole "enter the artefact" part.

Later on, I did encounter the floating artefact again in the inquisitor room, but with Vlaakith gone. So I could then still enter it and talk to the protector afterwards.