How hard is it.....
Ok, firstly you need to know what your policy says. Secondly, you need to contact your HR dept to get a copy of your summary plan description. It's a book all employees are entitled to, and it will tell you what is covered and what is not. Under exclusions - it should say gastric bypass or something similar if the gal at the surgeons office is correct. It should give a little description of what exactly is excluded, and if there is even a teeny tiny bit of ambiguity, this is what you use to fight them on. I think you should get the surgeons office to submit the request. You can't fight a denial if you aren't denied, right? It's not denied if it's never submitted..
Is it possible for you to give up one of your jobs and find a job which covers the surgery. Places like starbucks cover it and offer it for their parttime employees, I think Home Depot covers it, I don't know what you do for a living, but many people found new jobs to get insurance coverage for surgery (myself included). Banks, hospitals, some school districts. And as you are probably aware, just because you have Health Partners or BSBS and they cover it, you have to make sure your individual plan covers it.
You have to be your best advocate, you are the one that cares most in the world if you get this surgery, not your health insurance company, not the surgeons office, but you.
Best wishes and good luck!