So, hypothetically...
Let's say someone sent a package from Canada>USA that didn't arrive. It was sent in a thick envelope and would not have expelled any suspicious smell. It did not arrive despite have a few dollars worth of stamps on it. Is it likely to have been returned? The return address was an actual address with no connection to either party. If border services ended up seizing it, how thorough would their investigation be, keeping in mind the contents were not of an especially noteworthy nature? Is it possible it was just returned to the address listed as "return?"
In this hypothetical situation, would it be possible to check tracking information?