Then he has every right to do so. If there was a DNR and they did not follow it, then they should be sued. If they had followed the law on this, none of this would have happened and we would never have heard the name Terri Schiavo.
I believe you are mistaken. Guardians cannot use DNR orders to deny their wards medical treatment. Michael tried that early on, you recall, when Terri developed a uninary tract infection. As he later admitted in court, Michael ordered that she not be treated. That was against the law. The facility overruled him and gave her the antibiotics she needed.
What we learned is that Michael was not only willing but eager for his wife to die of a urinary tract infection -- every woman's nightmare. He knew she could feel pain and he knows enough medicine to know that this is a hideous death.
There was no DNR orders posted for Terri until her loving husband won the malpractice award. After that, there was no resuscitation attempt needed for Terri. Maybe you can make something else up?