Snap interview questions

This was a pretty weird interview experience. I applied, connected with a recruiter, and made it to the phone screen. There were two people on the phone interview, and one of them didn't say anything the entire time. The interviewer who did the talking asked me one easy SQL question which I answered pretty quickly, but the interviewer told me I had done it incorrectly. I thought my brain had died because it was a really easy problem and I had no idea how my answer could be wrong...long story short I ended up explaining to the interviewer exactly how my script worked, and at the end of like 10 minutes of very stressed confusion on my part she said actually that I had done it correctly. Then, one pretty easy Python question. Almost the exact same thing happened where she seemed to suggest that I was doing something wrong, and then at the end of my code explanation basically said "oh okay, I guess this is right". At the end of the interview there were some applied case study questions. I was rejected about a week later. At the time of this interview, I had done about 4 (very similar) technical phone screens at various large tech companies and had passed all of them. I double checked my SQL & Python code with myself & others after this interview, and they were confirmed as correct. My theory is that they didn't intend to actually hire me, and used me as interview practice for someone new to hiring? But even then, it was bizarre that this person did not seem to know the answers to the interview questions (or Python/SQL very well).