I think you bring up a good point here about filing based on emotion. I think these charges are objectively appropriate.

If an individual dies during the commission of a crime, the perpetrator can be charged with murder. The officer died due to complications of a surgery made "necessary" by actions of the perpetrator. (Medical necessity is implied by ADN coverage)

Objectively, I think the charges are appropriate if the surgery is determined to be medically necessary to return quality of life and the injury was obtained during the commission of a crime. Had the officer died during an elective surgery like scar removal my opinion would be different.