Tetrad Digital Integrity Software Engineer interview questions

The person I was meant to interview with did not show up until about 30 mins into the process. The employee I actually met with was a consultant, not an employee. The consultant and I discussed my career roles and I enjoyed talking with him. The hiring manager remained silent, and left before the interview ended. I was told that because I did not answer his deeper questions - of which there were but one, I was not offered the position. This is befuddling, as he asked one question the entire time, and was not present for the majority of the interview. It seems clear that this hiring manager simply did not care or had personal issues that I was unaware of.