Is possible septus, stage 2 bed sore and severe cal./protien malnutrition that led to respitory failure as immediate cause of death a natural cause

Thats what the coroner wrote on my mothers death certificate 6 months after a police report for elder neglect was filed and an autopsy was ordered and performed. The hospital where mom died filed the report. My mom was 81, disabled, bedridden and lived in her own home with her son. A doctor paid her house calls and ignored the health hazzards that killed her. The doctor was to visit once a month and practiced in elder care. I know my mom did not die of natural causes, i was granted emergency guardian by the courts and consented to a DNR with the hospitals opion to do so. Acute Respitory failure is not a immediate cause of death, its a syndrome of the factual causes of death that led up to the accute respitory failure. Which was malnutrition that led to unhealing wounds that caused septus. Surgery was performed, blood transfusion was needed and over fluiding led to accute respitory failure