Nope, you want to know whose fault it is? Yours. It is YOUR responsibility to get a certified saddle fitter out. As you said your mare has filled out which means the saddle would need to be changed. I am about to spend a total of $1500 on a decent saddle and pad that properly fits my TB. Your horse is still growing and will probably need a saddle fitter out at least once a year until she stops growing. Trainers don't have to know basic saddle fit its more a bonus and maybe that saddle did fit before she filled out.
Ok perhaps I am the one to blame, if it is then its a learning experience for me.
Originally I was going to get a saddle fitter. Do you remember before I moved to this new barn, I was saying how I talked with one saddle fitter and was going to have her out? (She charges $150). BUT she only comes and fits saddles on your horse, she doesnt go with you to the stores shopping (this is most likely why Ill call back the chiro from last night). I would prefer for someone to come WITH me to the store and pick and choose because Im not knowledgeable enough about saddles to go alone.
Then when I got to the new barn, my trainer said "lets try on this saddle" as we were browsing through the lesson saddles to see what could possibly fit and then she says its a pretty good fit. She even ran her hands and fingers along the sides starting from the gullet (exactly like how the chiro did last night) and said there wasnt any tight pressure points. Now, the very first time we fit the saddle on her, the BO did come in to watch my trainer get on my mare for a quick ride, but he did not look over the saddle. Perhaps Im to blame for this as well in not asking him (seeing how he knows a lot more in saddle fitting) but again, I trusted my trainers judgement when she said it was a good enough fit. But I cant be expecting the BO to be willing to check saddle fit because its not his job, I pay him to feed my horse. I thought what a blessing in disguise cause I have a saddle to use for the time being until I find out. Well wrong, cause look what its caused.
I figured my trainer just saved me $150 for having a saddle fitter come out, but really itll cost me more because $100 for last nights chiro and mostly will have her out again in a month or so to followup, so another $100. Uhhh, plus more to finally get on with saddle fitting.
And you are right, PERHAPS my mare did fit into this saddle 2 months ago but has filled out since then. Possibility but fill out that much in just 6 weeks? Not sure. Even though the massage therapist did mention (when she was out 2.5 weeks ago) that she has gained noticable muscle in her topline, back, front end etc.