Acute Kidney Failure and what to do with unresponsive doctors

Hello everyone. Hoping to get some feedback here, as I have been trying to figure out the best course of action and my doctors have not been helpful. Background is I have hypertension but am not diabetic. I've never had kidney issues before, but suddenly about three weeks ago my GFR dropped to 14, creatinine was 3.9, and BUN was 72. I discovered these numbers after I was given Gemzar for stomach sarcoma for the first time, but although I don't think the Gemzar caused the problem, I think it made the matter worse. I was called back in to oncologist's office, told I was dehydrated, and given three bags of IV sodium water over a few days. They never did blood work before giving the Gemzar and relied on old numbers. Now three weeks later the creat has hit a speed bump at 1.7, BUN at 37, and GFR at 37. I have asked for a referral to a kidney specialist from both oncologist and primary, but neither is interested in doing that with the oncologists just wanting to plow ahead with Gemzar and Taxall, and the primary just blowing it all off. He wouldn't even do a urinalysis. I saw another oncologist on my own who told me not to take any more chemo until I had some idea of what caused the kidneys to fall off of a cliff. Unable so far to get a referral for renal specialist even though I'm fully insured. We've temporarily stopped the chemo. I'm thinking that was not a good idea because this doctor takes weeks and weeks to act. I am experiencing shortness of breath, muscle spasms/twitches, lower back pain, occasional chest pain, fatigue. Your thoughts/suggestions please.