PANAMA CITY, Fla. — Ceely Taylor had not seen her fiancé in two days when, frightened and worried, she went to the authorities. In the chaotic days this month after Hurricane Michael struck the Florida Panhandle, he had somehow vanished.

But by the time Ms. Taylor described Dakota Brooks, the 6-foot-tall steam plant worker she was engaged to, to a police investigator, he was already dead — killed not by the hurricane’s ravaging winds or storm surge, but by a state law enforcement officer who may have thought he was a looter.

It took days for Mr. Brooks’s friends and family to learn his fate in the frenzied aftermath of the Category 4 storm, which killed 19 people in coastal Bay County and left hundreds of families searching for missing relatives — hampered by downed power lines, unreliable cellphone service and shaky internet connections.

Witnesses said Mr. Brooks, having gone out for a walk after the storm, was spotted after rifling through cars and scuffled with a state law enforcement agent in the moments before he was shot. For Ms. Taylor, though, that does not answer the questions that trouble her most: How could he have survived one of the worst storms ever to hit the Florida Panhandle, only to die when it stopped raining? And why, when she had barraged the authorities with questions about her fiancé, did it take days to learn that he had been the victim of a law enforcement shooting?