Asymmerical measuring limits
Go with Employee A. Look closely at the idea of firing Employee B. The critical factor is "Results in possible product failure".

Why is there any doubt? And what sort of customer will approve such a decision? The term "clueless" comes to mind, but I'd be interested in other opinions.

There is simply nothing sacred about having symmetrical tolerances. If you must have such, specify 23.5 volts nominal, with +/- 6.4% tolerance.