Labcorp Sales Representative interview questions

I have a friend who works there and got my resume to the top of the pile. I interviewed with the screener and passed to the next step of the process. I met with a manager who was interviewing reps for the role as there was no manager for the territory I was interviewing. She closed me before I had the chance to do so, telling me I would be moving along in the process to meet her manager. 3 days later, I received a generic rejection letter. When I wrote the recruiter asking why I was rejected after I was told by the manager I would be moved along to meet with her manager, it was very bland, generic. I wrote again, asking for more specific reasons why. That email was unanswered. The hiring manager told my friend she had no idea why I was knocked out of contention and she approved me to meet with her manager. My friend reached out to people in his network but never found why I was bounced. I find it repulsive that I wasn't given a proper answer; ESPECIALLY after a referral had advocated for me.