It shouldn’t matter, a bad cell is a bad cell and it will show up immediately as soon as the load starts and the battery drops to sub 9v. If the battery is weak, it will recommend to charge and retest. But they shouldn’t test the battery if it’s below 12v at rest anyway. Gotta watch those high school parts counter kids! Lol
The battery test machines they have nowadays are pretty slick. There no reason to grab your voltmeter anymore. Just drop the batts off and wait.