Used hallucinate attacked golem - buff went to clone and was gone on its death. possibly same can happen with lizard dunno.
oh and one more thingy it would be nice if when lets say u get buff or have buff and use hallucinate that the clone would also have it since if u have it hallucinate and the other dude does not have buff circle around its pretty obvious which one is fake :/

There is a known issue with buffs and Hallucinate. Positive ones stay on Shaco, but negative ones get moved to the clone on cast.

As far as earning the buff is concerned, maybe when you get close to killing the golem (lizard) move the clone away so you get the killing blow instead of him?