[Quest] BRD AF3 Bugfix

[ThrisStraizo]

I affirm:

• I understand that if I do not agree to the following points by completing the checkboxes my PR will be ignored.
• I understand I should leave resolving conversations to the LandSandBoat team so that reviewers won't miss what was said.
• I have read and understood the Contributing Guide and the Code of Conduct.
• I have tested my code and the things my code has changed since the last commit in the PR and will test after any later commits.

What does this pull request do?

This PR adds a safety check to Bugaboo's death so multiple players attempting the quest can't hard lock themselves from progress if they checked the altar before helping a friend defeat the ghost again.

Steps to test these changes

Kill ghost, turn in KI's at altar, kill ghost again. Progress as normal.