|The taken pup is t he one on the left.|
Update 7-23-2016: The toppenish police department retrieved the pup and I picked it up last night. The pup is happy to be back with its little friend after a week-long adventure.
The man who took the dog "thought that it was a stray" and intended to keep it. He didn't contact anyone about the dog or ask about it at the auction. The police department said that since there's no footage of him opening the trailer that they're be a problem at trial, and honestly I'm just glad to have the dog back, so I think this will end it.
And I'm going to get a tag for the pup and have him microchipped.
This is a followup to a previous post
A helpful person on the internet was able to figure out that the last 3 digits in the license plate; 23N the 2 and 3 are pretty clear, the N is probable.
Turns out that someone at the auction knows who the owner of the truck is and provided the deputy investigating this with the name, address and phone number of that person. I don't know that the owner of the truck is the person who was driving it that day, but it's a great lead.
The deputy is on her way over to the auction yard now, and I suspect that there will be some movement in the case in the next day or two.