MHC KENWORTH Ridiculous overcharges Cheyenne Wyoming

On 7/25/14 my transmission in ky kenworth went out..Called kenworth and spoke to them regarding wait time for repairs and such. During the conversation asked them if they had a tow company they worked with.  They said yes and it would be no problem to add the tow bill to repair bill for convenience.There was nothing said about a charge for this.   Keep in mind that I called the tow company and made all arrangements.  Kenworth only gave me the phone number. When the repair was finished and I received the bill there was a tow bill for $783. This seemed out of the norm for a 16 mile tow so I called the tow company and asked for the amount they invoiced. $375. For some reason kenworth thinks they deserve  $408 when they didn't even make a phone call. .I was told the person who made this decision is out of town for 2 weeks and would call me when he returned. A month later I'm still waiting.