Is her saddle too far back? Ladies need to take more weight through their legs when pedalling to relieve pressure. A saddle mounted with knee over pedal at 90 degrees is a good start.
With respect, I’d expect this is more likely to be part of the problem. Can you expect someone to take more weight through the legs when pedalling, as the legs will tire while riding? Suitability of bike fit and saddle are more likely to do the job. KOPs isn’t really a starting point for good bike fit, more of a coincidental outcome or a basic guide for men on 73 parallel racing bikes.
She may well be tipping forwards too much. As someone said earlier, start with a more rearward saddle to get her weight back, more likely to give a neutral balance on the bike for comfort. Weight back via saddle position will mean she can raise the bar or bring it back (or both) without affecting her balance much, so the sitting position can be adjusted to be more comfortable.