This really doesn't seem like a QA problem to me (a professional QA) , it seems more like a pushy boss problem.
If it were a QA failure you could expect other related defects as they tend to cluster , this is because very few functions are totally isolated so if you have defect in a function its likely to effect others. In this instance i would expect lots of charge failures or rapidly depleting batteries in devices that had less serious variants of this defect.
Where you have a single component over specced and rushed to market thats something a QA is going to flag , but they can't fix it , the person receiving that flag was told about this and decided to sign it off as acceptable risk and lots of people got burnt, some more literally that others.
QA is only as good as the management lets it be