Things I'd do if I were her doc (with the big caveat that I'm an MS4 going into psychiatry...) if your current doc won't do these things it shouldn't be too hard to find one who will be willing:

Blood work (tsh, Esr, RF, etc)

Urine culture (referred pain from a uti isn't too crazy)

Pap/gynecologist referral (lots of gynecological issues can cause referred hip pain)

Imaging (depending on clinical picture)

Physical therapy (most common etiology is MSK)