So I went in after the ranger and killed motor-runner and this prompts the message that i've failed aba daba honeymoon.
The message didn't come up directly so I saved right after killing him. I've got no saves to fall back on, I deactivated saving
on travel for stability. I've tried setting the quest stage to 10 (find anders) but the console shows that the quest is set to stage
70 as well (quest failed). How do I "unfail" the quest?

Nevermind, after some more digging in the vault wiki I found a command to simply reset the quest, I revived Motor-Runner first.

ResetQuest

If anyone has had a similar problem.