The 'funny running', vomiting and urinary complications make this more complicated by far. I'm just going to address the hip dysplasia issue as if it were the only problem presenting:
There are a huge number of publications in the scientific community addressing hip dysplasia in dogs and various treatments. It is not unusual for different doctors to offer different suggestions, options or combination treatments. It's a highly debated and controversial subject.
When young, under 1 year old dogs present with HD, it’s usually as the result of hip laxity which contributes to an abnormal gait that brings it to attention. Pain may present upon joint injury associated with this.
Many dogs may never experience significant enough signs of involvement to ever warrant diagnosis. Others are diagnosed, but can live entire lifetimes without significant disability or pain. There are a number of cases where a young dog is diagnosed upon symptoms as outlined above and then spontaneously remits and returns to normal function without any medical intervention.
There is a known poor correlation between the radiographic signs, symptoms and clinical functions.
Non-surgical treatment reviewed by Johnston (Vet Clinics North America 22:595-606, 1992) advocates physiotherapy with controlled exercise and strict confinement (to increase muscle mass/soft tissue support for the joint). Socialization problems may ensue and this can be serious in itself.
Treatment with NSAIDS for pain relief, chondroprotective agents like pentosan polysulphate (Cartrophen) and Adequan may also be options in a younger dog. There are isolated studies (without long term follow up) showing results with intramuscular injections of PSGAG weekly for 6 weeks to 8 months (Lust G et al AM J Vet Res 53: 1836-1843)
The botXXXXX XXXXXne is that you need to trust your animal caregiver to work with you in pursuing the right treatment options and symptom care. The severity of HD, individual animal and all other considerations are vital to any successful outcome.
I'm not sure if your caregiver/vet had such a disappointing prognosis because of something else going on with this pup (vomiting/urinary) or ???? I would absolutely have a 2nd opinion and possibly a 3rd.
Let us know ok?