My girlfriend is a lab technician at a small pharmaceutical startup. She created a very important Excel file and placed it in a shared folder on a server that the "IT" guy set up. The server runs Mountain Lion (OS X 10.8.2).

Last week, this important file went missing from this particular folder. There were several other files in this folder, but they didn't go missing.

She has since been able to recover the file from Time Machine, but wants to know how that file went missing. She assures me that no one in her department is careless enough to delete the file, but perhaps a higher-up with access to the shared file either accidentally moved/deleted the file (or did so deliberately due to the file's contents).

The issue here, is that due to a power struggle within the company, she suspects that someone may have attempted to sabotage (delete or move) this critical file which had data that could move the company forward faster in a particular direction than certain saboteurs would like.

The "IT" guys doesn't know much about server logs, etc. And I'm not a Mac expert. My question is this:

Is there a way to find out who deleted or moved this critical file? Are there file change logs located somewhere on the server that could "prove" this action?