I expect anytime one makes a special request for services outside of the norm of the contract it stresses the system. Good Sam does a lot of good or they would not be in business and supporting this website for us directly/indirectly (yes I can see the ads). These kinds of services for the DIY types can stress us. A person on the ground with a smart phone has more resources to get services, etc for their owe RV that they know inside and out. Clearly many prefer the comfort of a service like GS. Had you let them tow you to the nearest service center I expect it would have been done in a timely manner. Finding some management on the weekend to approve a non approved service would not be easy in many places of businesses.
Like you I would have wanted to get the sucker home to address the radiator issue. Most would not because then they would have had a tow bill to the repair center after they got it home. While I would not have liked to pay $492 to get the MH home at least it would have been home. In your case maybe there was a repair place 10 miles from where you broke down in the wrong direction from your house.
Sorry you had a failure. Do you see how it complicated things when you asked for a service they did not typically offer. Your initial logic was OK but outside I expect of the GS Rep training manual.