Infinitesima Senior Systems Engineer interview questions

First round video interview with technical manager, second round technical interview including presentation and meeting the team, third round interview with HR for cultural fit assessment. Negative experience at the 3rd round interview. Interviewer was 20 minutes late due to technical issues and the interview never really recovered. Very stilted from that point on. Not willing to discuss flexitime or compressed hours. Would not negotiate a salary within the advertised range and kept trying to find my current salary (basic interview technique is to never disclose this). Misinterpreted some of the wording I chose. Unfortunately, a negative experience based on this step.