Well, considering that Drive Knight told Genos and now this Hero Association guy about Dofoi being their enemy, I can think of two broad possibilities, and regardless of which I still think that Drive Knight is part of the machine group(forgot its name) from which the G5 and the others are from. That group has been in and out of the story since the Skin-Head incident (where the bald guys stole the suits from a place affiliated to the machine group and they showed up to kill him).
1- He's telling the truth. In this case he's either a runaway from the group or he's still part of it, but disagrees with the group's goals. For this possibility, I see Bofoi likely being a part of the Machine group.
2- He's lying or playing with words. What he said about Bofoi might still be true, but that's beside the point since in this possibility I see it as him being loyal to the Machine group and Bofoi having separated himself from it. Here it's possible that Drive Knight is trying to change the focus entirely toward Bofoi so to have the heroes take care of Bofoi for the Machine group without them needing to do anything (and maybe the Machine Group are actually feeling threatened by Bofoi and aren't able to deal with him by themselves due to him being too cautious).
I guess it could also be a mix of any of the possibilities I mentioned within each of the two broad options. (such as option 1, but with Bofoi and the machine group's relationship with each others being like I said in option 2)