I think I mentioned at one time before (who knows where now) that I could believe a scenario where Randy was one of the lab guys or lab techs at Raydon that worked on Ink's research team.

Since we aren't really sure of Randy's motives at this point (with Ink or against Ink), it might be hard to go deeper into this idea but I could see it playing out either way:

1) Randy is with Ink: he liked his boss and never really believed in stories about the murders/etc. When he turned and found out about Ink/Roberts, he naturally went to him and "enlisted"

2) Randy found out about some bad juju going on at Raydon with Ink's work. He suspected something earlier but when the news of the murders came out, he knew something bad was up with the research. He didn't know about Ink until after he turned but, being a very Smart One, Randy was able to keep a hold of his human side and decided to try to thwart Ink's plans.

Or any number of things like that (apparent I have about a 5% chance of one of these being right....)