[SKM]

My understanding was that when a dealer or wholesaler makes an offer to buy a car, they can, and will, actually write the check and buy the car.

Your approach as a bird dog appears to be different. You state a low price, enter it into the "system" of your dealer, order a PPI, work down your low price offer to a lower price based on the PPI result, read the seller your sales agreement, and then perhaps your dealer buys the car.
Since you did not explain any of this to me, I did believe that you were making an offer. My mistake.

I did ultimately sell the car to a dealer who made an offer and wrote the check on the spot. No B.S. such as entering the car into a system, etc.