Can I sue my developer and builder?

I am a disabled veteran and I bought a new home where a dog park was promised. This was crucial to me because I have a service dog. The developer is now refusing to build the dog park. I've been told by the county that the developer never got approval for a fence and since they've granted the county authority to cite anybody violating leash laws, this would be necessary for a dog park where it's advertised that you can play frisbee and chase with your dog. One attorney told me that since I have a separate builder and developer that I can only sue the builder because that's who my deal is with. Another attorney told me that I can sue both the builder and developer and that he will subpoena the salesperson who gave me the brochure with the dog park promise as well as told me there would be a dog park and call other homeowners to testify that they were told the same thing. Which attorney is correct?