Not a black leopard. What he encountered is a Florida Panther.
Its the same species as a Cougar, Puma or Mountain Lion but in Florida they’re called Florida Panthers. The state brought in some from outside to freshen up the gene pool of them just a few years ago. Getting close to them is an exceptionally bad idea.
If the Florida Fish and Wildlife identifies the cat as a Black Leopard you can be sure it was indeed a Black Leopard and not a Florida Panther. They pretty much know the difference.