Crash can be difficult to trace because it sometimes happen without getting logged. I guess the most useful information you can give is what you were doing before the crash (what server, what kind of match was it, what faction, what map, etc), your operating system, some info about your computer specification, your credit card number, the expiration date, and the three digits on the back.
Personally the only crash I've ever had in MP is when I was playing around the character creation. I've never crashed mid-game. I only play on East Asia servers tho.
Ah right. Sending MArdA your log (C:/ProgramData/Mount and Blade II Bannerlord/rgl_log_bla.txt) might be helpful too. He helped fixed my login issue with mine.