Well first of all, I hope you get better! I work at a hospital doing CT so I see neck/back injury people every day and I wouldn't wish spine/nerve issues on anybody. Second, I think your thread title would make a great blues song!
As far as paying for your MRI, I take it you have to pay out-of-pocket for it? Most of the places I work will DEFINITELY deal with people on the cost, usually the business office people start out saying they want $$$$$$ but will definitely change that in different circumstances. Also nowhere I've been has played "hardball" as far as billing, I've heard of them agreeing to $5 a month afterwards, just to get SOMETHING coming in from the scan. My most recent job, (that I got laid off from...go figure) had something like 55% of the patients they treated, completely ignoring the bills afterwards-we got 0 from more than half the people we saw. Just ask, it can't hurt to find out. Oh and an MRI is completely non-invasive so just seeing what exactly is going on in there can only help.
That being said, before getting operated on, GET A SECOND (or 3rd) OPINION! Especially with your spine! My mom is on her 3rd lumbar spine surgery, she went with her usual family Dr and who he recommended for the initial surgery, had NO improvement, had to go to a different surgeon who had to totally revise her fusion (first guy did 3 vertebrae, and guy #2 said it should have been all 5) Now a year post surgery, her symptoms are coming back (numbness, weakness, bladder "issues") so REALLY make sure whoever wants to cut you up knows what they are doing and is GOOD.
Good luck, I really wish you the best with this.