OP, have you considered seeking employment as a apheresis nurse minus the dialysis? I mean, find a job just doing apheresis, get trained, work there for a period of time, and then try again to get into the acute dialysis program that you want to be in? I realize that this would mean changing employers again in a year or two, but then you would have the entire package that they are looking for and they should snap you right up.
On the other hand, you may find that you really enjoy the apheresis position and want to stay there. Honestly, it doesn't look like a bad gig, I remember the apheresis nurse from our local Red Cross coming in and running patients when I was working inpatient med/surg and she loved her job. She wasn't dealing with chronic renal patients and all of their "idiosyncrasies" (to put it diplomatically) most of the time and she highly recommended her job to all of us burned out med/surg nurses.
I'm not saying that just because that nurse liked it you would too, just maybe something to think about since you seem stuck between a rock and a hard place right now. I don't think you would have any trouble getting hired because of your recent dialysis experience, and they would certainly train you as most nurses don't have apheresis experience coming into it. As I said, the Red Cross hires nurses for this type of work, I'm not sure who else but you could just go to a site like Indeed.com and do a search for apheresis positions in your area.
BTW, for what it's worth, I agree with you about D*****. I won't go into detail, but I will never work for them or F******** again. $$$$ over patients, just like so many other organizations these days.