Ok, so I had a boxer before I got an EB. Does your boxer see the same vet or a different one? Have you done any internet searches into these extras your vet keeps recommending? How comfortable do you feel with this vet? I'm shocked they are offering all this extra stuff, as I've never had that happen with my boxer or with my EB. If you aren't comfortable with this vet I'd suggest you switch.
Don't know if this helps or not...Food for thought.
Edited to add:
Boxers are known for bad hips, too. If you know the breeder of the EB, what can they tell you about the health of the parents and grandparents of your EB? That has always been the indicator for me as to if they will have hip problems in the future.