I hope all your things arrive, but this sounds very similar to a large scam about the same time last year by a person.
He first built up many clients quickly, many listed great reviews, then over the holidays the EXACT same thing of him sending everyone TNs that showed things arrived at the depot for sorting/dispatching.
But they then sat there for days and days and never moved. No ones moved, ever.
He had created the TNs using the shippers software and this allowed TNs to be generated that would show what looked like the letter was dropped of and received by the shipper.
They never moved.
They guy continued to tell others he was baffled too, it allowed a few extra orders to be placed by others before the scam was revealed.
After 5 days of no movement, Bull Shit was declared and the scam was exposed.
I'm curious what the receiving location is and what your TN's show, and would be curious of the area this vendor is in to see if it's the same area as last years guy. He is for sure still around, he had a dozen different names and for sure would scam again after making so much last year.
If someone wants to PM me the shipping details, location things are stuck in and what the TN shows I would be happy to compare it to last years info that I still have.