I work for a company that uses Arrow trucking for our shipments. We had some large transformers being shipped from the plant to the job site, that are now missing since Arrow shut their doors.
If you know more or less where your shipment was when the driver was told to turn in his rig, you might put out the word at local truck stops and dealers in the area offering a reward for info on the location of your trailer. Someone will know where it is, and will be able to get word back so you can get another tractor (and maybe trailer) to finish the delivery.
I’m no legal expert — especially not on freight transportation matters. Which entity is legally responsible for a load in your situation: the shipper or the carrier?
What’s the insurance situation look like? Yours or Arrow’s cover any of it?
The customer must be going ballistic, he’s got a construction schedule and no G*D* transformers, huge loan payments and probably a hefty performance bond. Man, one irresponsible shipping company can make a world of pain.