Some of the citations have more than one set of related paperwork, signed by different SecNav. I wouldn't put much into that, other than Kerry was anal about making sure his "hero" record remained, even if he threw medals of the fence at the White House, etc.
Even at Kerry's web-site, the various versions of the awards are posted. The awards are not identical, FWIW. In one, the word "calm" was excised, going from the early version to the late version.