Not sure what your mom’s overall health or hearing ability is, but based on my own experience of wearing aids like 30-odd years, in the final analysis it really doesn’t matter what order of tests are done to initially set up the aids and program them for the hearing loss curve.
After wearing the aids for a few days your mom will likely know what she doesn’t like about the sound quality. Maybe it’s not being able to hear well in noisy places, or wind noises, or she’s missing high frequencies or even lower ones. Maybe the aids sound tinny and flat or BOOMING. And this is where the true journey begins, cuz her audi should be a lifelong companion and techie to work with her over time, adjusting frequencies, gain and even programs for different listening environments. She may want a TV Connector to stream with a TV or laptop, and perhaps even get her aids paired with a cell phone for hands-free, stereophonic phone calls.
Thing is: the aids are RARELY EVER set to the perfect sound experience no matter what kind of tests or measurements are taken up-front. So prepare her for the reality of follow-on visits - maybe even a half dozen or more. All part of the process to achieve optimum hearing as your MOM wants it to be - not dictated by some audiogram or measurement. It’s brain + ear that equals listening pleasure and comprehension.