No, because you're not sure of whether or not Gheb himself is Kira, while statistically not, it could be giving him one free kill PLUS assumption that he isn't Kira. He wouldn't even have to jump the wagon because the possibility of everyone else doing it. Effectively giving him town cred while still giving him a kill. IE, you're not giving pressure.
Other way around being that I'm Kira, why would I focus on only one subject? If people agreed with your Gheb case I would drop it. There wouldn't' be a point to continue down a road that would only give me bad cred in the future plus a possibility of losing the game because of the incorrect id of Gheb. IMO Kira won't be part of this game that much, he'll be watching but not actively participating until someone's about to be ID'd incorrectly.
#My2Cents