What would a productive response be? I agree that getting unnecessarily mired in drama is counterproductive, but I don't think that these accusations could have been reasonably ignored, nor do I know what Rod could (or should) have done differently.
You need to not be accusatory, nor defensive.
This is the age old way of dealing with issues in a productive fashion. Read getting to "Getting to yes" or try getting married.
What I read in this github issue is just immature, very ineffective problem solving from I guess someone who doesn't know better.
You don't like to hear the defense, all right. Just don't try to stop other people from hearing it.
Only if you want to run a negative sum game for all involved. This is a horrible strategy to engage in. You only end up also wrecking your own reputation and others and wasting a ton of time.
The socially mature thing to do is resolve this behind closed doors and be flexible as I suggested.
He may get some success by playing the martyr, but it will be success that occurs by his aggression, stubbornness and by expending more efforts in polemics than others. In the end he might still be standing but everyone around him will be wounded metaphorically because of this (mostly via huge wastes of time because of difficult conversations and departures of people from the project.)
Anyone who wants to run a company focused on results and to avoid unnecessary drama should avoid this type of character like the plague.
This behavior he is currently engaging in is a huge red flag if you recognize it for what it is.
Again, he is engaging in a strategy that forces everyone into a negative sum game, which is itself a form of aggression -- and it is easy to recognize from this github issue as I've seen this before close up. It is not a smart thing to do and should have been avoided by doing things differently long ago.
He can still pull up by basically retracting all of this and re-engaging in a mature and flexible manner that shows some contrition/empathy -- but that requires a strong ego, social maturity, and flexibility which may not be something that is possible on his part at this time. Everyone he is dealing with would love that I am sure, even at this stage, because it will stop the negative sum game.