I’m not quite ready to raise the hoax flag but there are a couple of aspects to this story that don’t quite make sense. I’m having a lot of trouble with CBP making the phone call in the first place. If indeed they were somehow alerted to an ongoing investigation I doubt they would tip the government’s hand by making such a call. I had a subordinate who, along with her husband, was under FBI investigation for contract fraud. Nobody in our agency knew anything about it until her husband was arrested and charged. We immediately went to the FBI about potentially removing her from her position which involved Federal contracts. They basically told us to “sit down and stay out of the way”. We were directly and firmly told we should take no action and say nothing about this to her. In hindsight it became clear she was a suspect and still under investigation. Turned out she wasn’t involved at least not to the point where any charges were ever filed against her but her husband spent seven years in Federal prison. I find it hard to believe that the OP has not been questioned by the FBI, USPS, or DEA prior to CBP making a call out of nowhere.