So sorry, snowball. 
I too suspect the package was emptied at the store or even before that.
I would not be counting on any surveillance at a UPS store (independently owned). Some places do have surveillance; luxury department stores apprently have protocols for handling more expensive merchandise and surveillance in their shipping rooms because some thieving employees used to “legitimize” fake goods: in the shipping room, someone would swap that real Gucci bag for a fake one and ship the fakery to the customer. Then the thieves would sell the real deal on a resale site, and the customer will have to prove to the store that they have not swapped the item themselves. I once ordered a black designer dress that was deeply discounted, and the package came in with a black nightgown inside, even though the shipping slip said there was that black designer dress in the package. Took it to Neiman and got a few glaring stares from the clerk who refunded my money and said they would look into who could have possibly done it.