Mythic Sennarth Spawned at the top

Seeing how far I can solo mythic VotI → Got to Sennarth and cleared the trash to summon the boss. And the add spawned, but Sennarth just didn’t. I could target her but only saw her ‘hit box’ and not her actual char model.

I pulled the add and the boss immediately reset.

Same thing though. Add there but boss’ char model was not.

I eventually look up and see her just sitting at the top.

So, I pulled the add to see what happened. Boss didn’t reset. However, I had to run all the way up to the top to hit her.

Though, weirdly, her char model was up at the top but the hit box was moving up the arena normally. Though in order to dmg the boss I had to hit the actual char model and not the ‘targeted hit box’.