Of course they are 'different' but not worth an extra $200.
You might want to look for another shop.
I see you are from my old stomping grounds. I took my then new 97 Bounder to the place with a big 'bear' on it along Garden Grove Blvd and had the front end aligned when it was only about 4 months old, and the springs had gotten used to the load that we put in the RV. They asked 'why' - Fleetwood did a front end alignment to all the new RV's.
They made a small adjustment, and I never did have any problems with the front tire treads looking great after 7 years, and 20,000 miles. Then I would need to change the tires anyway.
It was between Magnolia and Brookhurst. I lived at Magnolia just south of Garden Grove Blvd at the time. The name is Vodie's and according to Google maps, they are still there. 9891 GG Blvd. Stop by in your car, and ask about the Ford motorhome chassis. They probably can help you out for a reasonable price.
It is a huge front end alignment shop, and they where trained to do front end alignments on large trucks. Back in the 60's straight axles like mine where 'bent' to adjust the camber. Now Ford claims it is 'factory set' and can not be adjusted. Well any normal shop will not attempt to adjust it, they are not trained as to how. This shop has the tools, and clamps down the front axle, while using a 20 ton jack to adjust it to make the tires stand up straight. This really helps in the tracking.
If they can not help you, they probably know someone who can. . . I just hope that they are still in business.
Fred.