Our procedures require that in a case of closure by mail, the box is opened in the presence of two people--one of which is an officer of the bank--and a notary (if one of the two is not a notary) just in case there IS something inside and the box must be inventoried. What if your single control employee opened the box, felt the weight, took a peek and found something to interest them and took it, put the rest back, and then came to you and reported that the box was heavy so he/she put it right back and came straight to you? The customer doesn't remember anything anyway so they won't miss what I took, right?
Or worse!! I just thought, "What if this were my ploy to bilk the bank out of easy money?" Why not claim it empty, some goes in to close it out and finds something, contacts me, and I say, "Oh, I forgot. I had such and such and a diamond ring worth $10,000." Well, you go back and inventory under dual control and see the such and such but not the diamond ring, so you go back to me and report your findings. Now I claim that your employee took it when they went in by themselves, EVEN if your employee didn't take it. What leg do you have to stand on? I will get an easy $10,000 if I am legally savvy.
If we couldn't get two people to examine the box upon receipt of the letter, the key would be immediately secured under dual control until such a time for dual controlled inventory.
i would inventory it under dual control fast and hope for the best.