My saddle fitter never did tracings. I have bought two saddles through her and she adjusts them and a third saddle as needed.
I don’t know what your fitter meant by dynamic fit but mine likes to see the client ride in at least two saddles so she can see how the horse behaves and moves. The comparison is key. When I was looking for a jumping saddle (my first experience with this fitter) she brought a dozen saddles out after I’d sent an email with information similar to yours (what saddles I’d tried, why they didn’t work, what I liked and disliked about various saddles as a rider). Most of the saddles were put on my horse’s back and checked for fit. A couple were rejected without touching him. Two of the saddles looked like good fits, one of which looked to have been made to exactly fit his back.
I rode in one saddle, then the other, changed the pad and rode again, then the first one again. With the exact fit saddle he would not take any kind of stretch spot at the jump - it was perfect or chipped. With the just good fit saddle he’d take whatever spot quite happily. The panels may have been a factor; one foam and the other wool.
On the flat it was very subtle but I felt he was more willing to lift his back and give the full effort/range in things like lengthening and collecting and lateral work. Seeing how my horse went with each saddle allowed the fitter to observe his comfort and freedom of movement and compare.
When I needed the next saddle the horse in question had a difficult shape and she brought me three saddles and three saddle trees. One saddle was rejected after sitting it on his back, the second after a five minute longe, and I actually got to ride in the third though only at a walk because he was mildly lame at trot. However after a few minutes in walk he was volunteering to lift his back and stretch his stride and reach into the contact. She let me have it to test ride for a week and I bought it.
In the years since she has adjusted the fit multiple times as his back changed with work (he is really particular about his saddle fit) and each time. I longe and ride with further adjustments as my horse demonstrated his opinion. My other horse never complained about his saddle, he’d just give less in whatever we were doing, so it was up to me to be really in tune with him and really put him through his paces and ask for everything too see how willingly he did it. My fitter knows that many riders aren’t that in tune with their horses which is why she likes to see them ridden.
What I’m saying is that you really have nothing to base an opinion on at the moment - just because the fitter said things that surprised you doesn’t mean they’re wrong. You aren’t commiting to purchasing a saddle from them - remember that! 
If you and the horse aren’t happy with a saddle then there’s no sale. Drop your preconceived notions of what should happen and go through this fitter’s process, and make your own evaluation of your horse’s and your comfort with each saddle. What your horse tells you is the most important thing.
