The only reasonable crime you the authorities might possibly could charge them is extreme negligence, not theft. You don't have any evidence for theft except your suspicion that this is an inside job.
There should be a proper investigation before we can speak about charging somebody, or did you lose your rationality when you lost your money?
FTFY.
People can certainly file criminal complaints. The extent to which those complaints are investigated and whether any investigations lead to criminal charges is another matter entirely and not determined by the complainants. People's theories (including mine) about what happened are not evidence.