IIRC, the story about that happening to MOBOs was that an employee from the PRC of a component company not in the PRC stole the formulation, and went back to the PRC.
They [PRC people] apparently did not follow the recipe, and/or didn't employ the same QC methods on input and output of the manufacture.
no, china had nothing to do with it, they were Taiwanese manufacturers.
an Japanese employee stole an electrolyte formula and sold it to the Taiwanese but he did not give them the right formula.
a much bigger problem, one which has cost much more is ROHS solder this is so serious that the dod has started another “Manhattan project” in order to solve it.