The mail forwarder responded:
We received an email from the **UPS** company where they explained that they are having delays because of the weather. Maybe it could be one of the reasons your package hasn't arrived yet (**_USPS_**) to your destination.
The problem wasn’t that it hadn’t arrived here in Utah, the problem is that it hadn’t been accepted into the USPS system in El Paso in the first place:
Hours after I asked if it had really been shipped:
Arrived at USPS Origin Facility 05/12/2020 12:10am EL PASO TX DISTRIBUTION CENTER Reply STOP to cancel
Occam’s Razor suggests the package was set aside for (needless) address clarification, was forgotten about, and wasn’t mailed until I asked about it days later.
Admit the error, then adjust procedures to minimize the chances of it happening again. A clever service provider would offer to cover/credit the difference between Priority Mail (what I paid $18.45 for) and normal ground delivery (what I am effectively getting).