ProBioGen interview questions

The first interview went smooth with four interviewers. The fourth interviewer was not mentioned on the interview invitation email though. They didn't mention salary during first interview and I did not either. After that interview, they immediately contact me via phone for the second on site interview in two days which was a bit difficult. Traveling for more than 5 hours to give an interview in short notice period. I was going on vacations from next day for two weeks as well. So, I politely asked to reschedule they agreed on phone first and then never contacted again. I tried to reach them out via emails and phones but they didn't answer. I also asked during that phone call to give me a salary range for this position before traveling to another city for an interview. They agreed on that, too. After a week, they simply rejected me with a general email. Perhaps, I shouldn't have asked for the salary range