There have been virtually no documented cases of pinholes from carbonate developers and acid stops or fixes. Eaton gives it a passing mention in his textbook but that is about it.
When a film is too soft and is hit by acid after a carbonate developer, the result is not a pinhole, it is a set of visible blisters. I have demonstrated this in my workshop to the students. The blisters resemble those on human skin from sunburn and when they dry they form either a fish scale like surface or an actual run of the emulsion.
A pinhole would not be a direct result of the release of gas.
I have also done this experiment in laboratory controlled conditions to determine if it would be safe to move from Kodalk to Carbonate in the EP-3 process (from EP-C). It had no effect unless the coating was too soft to survive processing without a whole series of other effects.
Besides, no film from Kodak, Fuji, Agfa or Ilford were that soft for the at least the last 50 years AFAIK.