Really? I'm sorry about your experience but mine was completely different, I scheduled my interview in the embassy in Mexico City and I just had to wait 1 week. It was a 2 day process, first I went to a CAS and they captured my biometric information, the next day I went to the interview with the consul which was like 15 minutes or less (but I had to wait for 2 hours), he only took a look at my employer's offer letter and asked for my cedula profesional and that was it. I got my TN visa 1 week later.