Regarding Piantelli's experiment ... I don't think that all aspects of Piantelli's rod Ni-H experiment carry over to Ni-H in general. In his rod experiment he uses a unique excitation means (thermal waves) that does not carry over into powder. I believe Piantelli has said that his experiments with Ni powder failed. So, would his H vs D result carry over to other Ni-H LENR? Maybe, or maybe not.
However, that experiment is probably largely responsible for why Piantelli believes that H is the reacting isotope.