SALINAS, Calif. - A former Harvard Medical School professor and a Boston art dealer who reported that thieves broke into their rental home in the ritzy coastal enclave of Pebble Beach, and made off with more than $27 million dollars worth of art, were named as suspects in the case yesterday. Police said Benjamin Amadio, 31, and Ralph Hennaugh, 62, were not cooperating with investigators and were unable to produce proof that the artwork even exists, let alone that it was stolen. Amadio said, “If we wanted money, we would’ve sold the art. It’s worth millions.’’