Hello and Good day.
So we've all played it, and annoyingly have to go through this everytime, and wonder if ZOS knows about it, and or is going to fix it, and it's an easy fix too. All they need to do is delete or move 1 NPC.
Tempest Island. Third mini boss, Stormfist. As you Exit the door directly after defeating the second Boss (Aka yalarosse the speaker). You enter the pathway leading up to the 3rd boss Stormfist. As you first make your way thru the narrow path littered with an enemy NPC camp, one lone NPC is stationed as lookout on the wall to the right. You cannot target him, and once you enter the zone, he reacts to your presence. He will then fall off the wall on the outside to which you cannot chase after him, and he will be triggered the entire time.
After you crush Stormfist, the 3rd mini boss, you make your way to exit to meet up with the final boss Valaran Stormcaller. However , YOU CANNOT open the DOOR because you are still in combat and have to crouch and wait for the cooldown. This is all due to that one NPC on the wall , right hand side, that slips off in the wrong direction. Some of us tested this theory, by throwing down all dots and ultimates, and jumping while trying to hit him and kill him. Once dead, combat stopped and we we're able to get thru the door. So either we can waste our time trying that, or crouch and wait about a minute if not longer sometimes, 1-3 minutes, but please Zenimax, just move the NPC on your next patch. Thanks.

In this video this is the example of killing that one , lone NPC that falls / slides off the other side of the wall. If I am not mistaken, I could have sworn that wall is an added feature because I remember , well in my mind, remember having to go on that side of the wall to kill some female Enemy NPC's stationed there.
Youtube (Full video) Exit clear at Stormfist due to killing enemy NPC.
https://youtu.be/wWDtB2hN9Bg
Youtube (Short video) Exit blocked at Stormfist boss due to skipping hidden NPC.
https://youtu.be/PXvvlaUgNpY
[This time I didn't Mime to fellow dungeoniers to kill the NPC that fell/slipped to the opposite side of the wall. Thus, door upon exit after miniboss completion, blocked due to in combat still. (Don't ask why I said that, asking me why didn't I just post in group chat. ZOS loves to make life difficult for me, is all I will say. Thus, I learn to mime) Haha.
ElderScrollsOnline Purchase History April 17, 2017 through May 30th 2022 (Crowns,Upgrades, ESO Plus) = $5,610.38