That's terrible! Have you spoken directly to Thor customer service? You need to get answers direct, without the middle man, your repair company.
Many RVers are DIY folks, and they would probably fabricate a temporary door our of plywood or a salvaged house door.
Your new door will be shipped as freight, and may take a couple of weeks after the ship date to arrive. Your RV trip looks like it will be a car trip! Bummer!
Bad decisions make great stories!