Ah, that must be it.
Diaz was executed by the state of Texas tonight, which recently ran out of the lethal drug pentobarbital supplied by a company in Denmark. Many other states have run out of pentobarbital as well, prompting some to put their executions on hold. But Texas managed to obtain a new supply of the drug from a mysterious unnamed source, so there was no change to their execution protocol.
Since Texas did away with special last meal requests in 2011, Diaz was served the same food as others in his unit. For his last meal, Arturo Diaz had Salisbury steak, steamed rice, brown gravy, mixed vegetables, corn, pinto beans, sliced bread, and a choice of lemonade, tea, or water to drink.