I'm not certain that "principle parties" matters much here, honestly, under the circumstances, especially when the actual comment offered has been very limited.
When it comes to the information available, there do seem to be no credible claims that the laptop's fake and credible claims that it actually was Hunter's, sure. There was initial doubt about its reality, of course, given the Republican clown show surrounding it, which gave rise to very real uncertainty about how much fiction is involved. As for altered, on the other hand - at last check, the current state of things was that some specific things on it have indeed been verified, but not any of the potentially more problematic stuff and that, given the evidence at hand about multiple rounds of later alterations in at least some files, it's impossible to validly claim that the laptop is unaltered. Rather, it seems far more true to say that the extent of alteration is largely unverifiable. It's certainly possible that the FBI may be working to investigate further based on potential leads from the laptop, but that's far cry from it being fully validated.