Think he was saying it is odd (and I agree) that something would be wrong at 51k that would require their taking the engine out.
I'd move on, even if they fix it I would rather have a vehicle with the engine intact from the get go instead of being put together by a local dealer. There should be plenty of 2010's to choose from.
2008 Acura MDX Tech + PTG - Steel Blue + Taupe - Traded in at 98,000 Miles
2013 Honda Odyssey Touring Elite - Smoky Topaz + Truffle
2016 Range Rover Sport Supercharged Dynamic - Firenze Red + Pimento