I completed "The Big Dig", Hancock asked me to kill bobbi, I didn't but i told him i did. Anyway, I need to talk to Hancock as Silver Shroud, but he only mentions Bobbi, I can't even add him as a companion, doesn't give me that option, after i rejected him. I can't even go onto a previous save, because the 4 it comes up all took place after this incident. Anyone know a way through?

Same here. I don't even get any dialog options. He just says something about meeting another ghoul. Annoying.

He has to be your current companion for those dialogue options.