Yard-birds, "eye-witnesses"....
As someone who's worked armed security/G in various parts of Florida(Pensacola, Palm Beach County, Orlando, Tampa, etc) I can honestly tell you, the "warning shot" will be taken completely out of context or you'll be unfairly accused of criminal misconduct by the responding LE officers & criminal investigators.
Some "yard-bird" or bystander will jump up when the PD shows up and crow about how
you were reckless or screaming threats repeatedly before you gunned down the poor helpless victim,
.
Warning shots(legal or otherwise) will make you(the armed citizen or license holder) "dangerous" & "unstable".
The recent "high profile criminal trial" in central Florida showed how that can occur. The Sanford FL police investigator wanted to put a manslaughter charge on the subject & build a police case saying he fired the Kel-Tec 9x19mm pistol "by accident".
If that subject fired a "warning shot" in that critical incident, there's no doubt in my military mind, the accusation of a "hate crime" or malice would be pushed further.
Witnesses can say what they want to LE. There is no requirement for them to understand the law or use-of-force statues.
Clyde