Can a dealership buy out a lease?

My getting a new car obsessed/fixated husband thinks that he can get rid of his 2010 lease with 15k miles and get a fast, sporty car. His credit isn't the best in the west, and they've asked me to co sign (good credit so far, but have a purchase on mine at the moment). He says the dealer said that they would love to buy his lease and would need a car like that on their lot. They said they will contact the lease holder, who is the car manufacturer. I smell a rat on this one. What is true?