If you're using an officially published primer sequence? Possible (due to supplier or user error), but _highly_ unlikely. We're pretty good at molecular biology at this point.
I'm not talking about making an entire test kit, but rather labs with existing RT-PCR abilities (ie the vast majority of molecular biology labs) having the appropriate primers and probes synthesized by the standard (non-clinical) vendors that they order from every day.
Without review, unscrupulous (or incompetent) vendors could make a test with unknown usefulness.