R129nut

I'm looking at a 2014 ML400 that is still under factory warranty. I was told by someone at MBUSA that if you buy it from the original owner you can extend the warranty. We are also looking at another MB that is also under factory warranty but was a lease return and sold through an auction to another dealer. When I inquired about the car that left MB finance and was sold thorough auction I was told that the warranty is no longer extendable? Does this sound correct? Sounds like MB is trying to protect their dealer network.