Randstad Recruiting interview questions

I was set up with an interview with an office manager via a friend of mine who is a recent hire. The conversation went well, and she even had me interview two would-be colleagues to get a feel for the culture and opinions of the other employees. We left on great terms, and I went the rest of the week without hearing from her, despite my sending a "thank you" email and a request to schedule the next step in the process. A week later, my friend set an interview up between myself and a more senior manager, and since she was given no details about the first conversation, this was basically a first interview all over again. Despite that, we had a great conversation and she put to rest any questions I had about the office environment. Another week went by, and I hadn't heard anything. I never heard from the second interviewer again, but I received an immediate response when I asked the immediate supervisor if I was still being considered for the role. She set me up with an interview with yet another person in the office, who had no idea who I was or for what position I was being considered. We spent about 45 minutes on the phone, and he said he had no qualms about moving forward with me and that they would be in touch regarding a shadowing session. Nearly two weeks later, I had again heard nothing. My friend finally had to ask at her one-on-one whether or not I was still being considered, and the short answer was "No." No reason was given, no feedback at all, and no direct word to me from management. Between the lack of updates, the lack of responses, and using my friend to convey their messages, the entire experience was unprofessional.