What is the most appropriate way to address someone being given a false PT score, while minimizing the damage to their career?

The truth shall set your free.

Falsifying a record to achieve monetary benifit should be dealt with immidiately as criminal. Investigate immidiately. Integrity must be kept in US Army.

Going by what you said, she already told on herself by not coming close to the 300 pts from previous APFT. Failing the following one says it all, unless she all of a sudden got injured, you didn't say anything about any injuries

Let's do an initial pft to see if you can still do 300 cause corporal course or no school is going to be impressed. So were taking the top pfters and see where they sit so after the promotion we can get them in a bit quicker to school. Play it that way it's not forcing anyone. But just a recheck and involve others who were top and pormoteable. To assure it is not a fluke. I had to prove I could do pullups for First Sgt. Since I was minimum on pullups to be a LCPL. No shame in proving if you can do it. Or have her suction as a whole do an initial pft. We had them all the time besides at Marines were always ready to do it for promotion. RAH!

Man up, come clean about the false score. And decline the promotion. Integrity will earn her more support than lying.

Step 1. Invent time machine.
Step 2. Use time machine to travel to moment before the decision was made to conspire to defraud the Army and violate Army values.
Short of that, the "SGT," needs to contact JAG for a legal opinion and options.
I'm not certain that you have a legal obligation to report this, it's the moral dilemma that you need to work through.

You have no role since she is in another unit now. Your previous role would have been to speak up when it occurred. You should in fact identify the person who assisted her and let your unit take care of that issue. She is wrong, as is the person who supported this act in her records prior to her PCS move. The good news is that she failed and will not be pinned if she does not pass. If her 1SG is in there job, he or she will realize their was something hokey with records and contact the losing unit, and from there connect the dots and bring about a fair and equitable solution for all who were complicit, including you. It does not take a genius to figure out that someone who recently scored 300 should not fail a subsequent test. What you may want to do to help your friend and you to get ahead of this is to tell her to come clean on the other side.

A great leader motivates. A good manager, organizes. I cannot say that this person is a good manger or organizer because the soldier obviously failed to plan for the APFT. I also cannot say that this soldier is a good leader either, because there appears to already be a lack of confidence from those concerned. From experience, I watched 15 people at Fort Hood all receive article 15s and rank reductions for cheating on their education records to score points under the old promotion system. I can tell you that your soldier not only deserves to lose rank, but also deserves to receive an article 15. What this soldier did was take a promotion away from an otherwise already qualified solder. Integrity means doing the right thing even when no one is watching. This does not mean that this soldier cannot bounce back. Some of the best leaders I've known in the Army have been demoted at least once, and these folks learned from the error, bounced back, and came out even stronger because of it. If you are looking for a way to whitewash this, you too are running the slippery slope of failing as a manager and a leader. Always remember one thing, no one fires or demotes a soldier. The soldier fires or demotes themselves.

She committed a fraud on everyone between her actual score and what was recorded. At a minimum she should lose the current promotion and on more stripe. The turd who lied for her, he needs to be fully investigated to see what favors he took from her, and then get a Big Chicken Dinner.

Put the turd back in her pocket. This is her mess to clean up. If she doesn’t do the right thing, then she is the turd and flush her. No integrity; no promotion. Simple.