Clearly it's waiting for the player's soul to escape.

Or maybe the NPCs need the player's soul so the NPCs can escape?
If you wait 10 seconds (the timeout value for Show/Hide animations), does it disappear? If so, make sure the dialogue panel has an animator that responds to the trigger parameter you've named in the dialogue panel's UI Panel component > Hide Animation Trigger. Or remove the dialogue panel's Animator component and clear the Show Animation Trigger & Hide Animation Trigger fields if you don't want a hide animation.
If that doesn't help, temporarily set the Dialogue Manager's Other Settings > Debug Level to Info. (
more info)
When you get to the end of the conversation, check the Console window for this message:
Dialogue System: Conversation ending.
If you see that, then the conversation is ending but the UI isn't hiding for some reason.
Also check for any errors or warnings in the Console window.
If you don't see the "Conversation ending" message, keep the Dialogue Editor window open on your conversation while you play. The current dialogue entry node will be colored green. This will give you an idea of where the active conversation is. Maybe it's getting stuck.