Definitely go to the ombudsman, I'm about to go there for the second time. Sadly it seems now that pet insurance is about companies doing all they can to worm out of payment, not paying fairly when you've sp a fortune in premiums over the years.
Whilst I tot agree that owners need to train their own dogs, I also think that live in training can be a great help and/ or work really well with specific issues. Training is a life long exercise but no harm in getting a helping hand.