job offer recinded after finding out about criminal background, protected under 23-A

I am located in upstate NY. We are protected by 23-A law here for discrimination against criminal background. I have never had a problem finding employment. However, I worked for an employer for almost 6yrs. During that 6yr period I left & returned 2x as a rehire, due to having a child and relocating. I was always immediately accepted, advised rehire policy states rehires are accepted over all other applicants, especially when my stats were the top of floor, meaning I am the best at my job proven on paper. This past time when I relocated back, the employer was not hiring, moving locations, & restaffing some. I accepted employment elsewhere & was there up until recently. I ran into the hiring manager from this prev employment, that strongly encouraged for my return since they are rehiring. Unknowingly at the time, a newly hired recruiter e-mailed me to apply & take assessments. I did apply afterwards, but not even knowing about that e-mail, & now knowing that it was due to the hiring manager. Afterwards, the recruiter called me 6x (I was on vacation) to let me know I was approved by HR to return, taking assessments were uneccessary, & to meet w/her as a formality, since the prev HR that handled recruitment in the past with me has left. I applied because my current employer had become unstable with hours & had switched to peice pay that was unmanagable, & I had to leave. (on good terms) I applied elsewhere, & had been offered a position prior to this recruiter calling me. Based on what I was informed, I turned down the other job offer, because I loved working for this company for the many yrs I have, & believed Id returned the same as in the past. I met with the new recruiter, they offered me 2 positions available, I accepted my old position, & they advised me Id receieve onboarding through my e-mail in about a week, which was new process as oppose to hand written documents in the past right then. The recruiter expressed relief that I was returning, advised me she was struggling to fill the 20 positions available, that only 1 other new hire had been approved, that she wasn't sure when training would start because she cant seem to fill all the positions. She let me know it may be a very tiny training class, that I'd be helping with, we joked. The new onboarding process done through an e-mail link contained the tax forms, id doc scan, background check consent, & drug testing form. I've always completed this in person, so I asked the recruiter who I would contact if anyone had questioms about my background. Let her know this was never an issue in the past, but since she was new, I'd be happy to answer any questions. She advised me that I'd speak to her afterwards, and so I duvulged the matter, knowing I am protected under 23-A, & that it was never an issue with this employer in the past. It was an isolated domestic violence issue with the father of my child. The recruiter assured me it was fine, that Id receive my onboarding info in about a week, and hopefully start training in about 3 weeks. I waited for the e-mail, but didnt receive anything, called recruitment, didnt hear back, was affraid it was going to spam. I am still in contact with many employees there, including management, obviously, and was told to call HR. I contact the new HR agent, not the same as I have dealt with in the past, & they informed me that the recruiter attempted e-mailing me to let me know she went with other applicants. This was obviously very strange to me, all things considered. I of course would be considered over any other applicants as a rehire, and since my performance was best, I would be considered over most rehires. I also know that these positions are not filled, that there are no other applicants to even consider. After speaking with HR, they fealt this did seem odd, and assured me they would look into it, or at least attempt to find out the real reasoning, since HR approved it, and the hiring manager is the one that encouraged me to return. I have not heard back from them yet, it has been less than 24hrs. What steps should I take if HR decides not to rectify this situation, since it is so obviously discrimination on criminal background?