I already talked to Motor-Runner once and I sold some chems for some caps. When I go to do this quest and try to talk to him again, the dialogue options don't open up. He says two different lines. My previous save was about four hours ago.

Did you kill one of the characters related to the quest? That is what caused it I guess.

No, I did all of the previous deliveries. I found the ranger in there but I left him there for now. He just rambles two different lines. I didn't kill anyone in the vault. I was there before and when I entered the vault, I said I had chems to deliver but I didn't start this quest till later and after I had already talked to him.