I don't think we know enough about him to go that far, Bill. Personally I think DE might be correct in deducing Ging's reason not to even visit Gon (not that Gon would know anything of it, being a coma patient), but that's still a far cry from being so cold he wouldn't care at all if Gon was killed. If he really didn't give a shit, he wouldn't have left the message in Greed Island. He would have just abandoned Gon and never looked back like a genuine scumbag.