I don't think it's the regional accreditation, but most likely the grading system. CRNA school is competitive as it is already and the untraditional grading system (3.0) wouldn't event be competitive enough for it anyways.
I graduated from the WGU prelicensure BSN program and i have friends who ask me they'd like to apply to the program that I did and I always ask them if they plan on doing advance practice nursing (np, crna) and if they do I always tell them to find a different program. I don't plan on doing any of those things, but I do plan on getting my msn but not in those areas. However, if you just want to do bedside then it's a good program. I could not have been a nurse without the untraditional format similar since I worked full-time.