You can find them IF you can see the dirt pile. There are a ton of glitches in the game that allow you to bury stashes and you cannot see the dirt pile. It IS a contributing factor to breaking the CLE. I have buried stuff set for 5 days on my server, infact everything is set for 5 days, tents, vehicles, stashes, you can put a lock on your tent, but you better check it in 5 days or poof.