Missing boss in report

Hi, I’ve uploaded a log as usual but I’m missing a boss; Iron reaver.

My report is https://www.warcraftlogs.com/reports/PGQmCJV8dpxj437z

Any idea on how to solve this ? I can see the Iron reaver part opening the log with an text editor.

Without seeing the raw log file, I can’t really explain why it would be missing.