We don't know what the Orlando PD policy is for an active shooter, but the game changer is when it became a hostage situation. If that is in fact what happened.
Sounds like the off duty LEO fired on the suspect in response to an active shooter, and the suspect lit him up heavy and retreated back inside, so the officer on scene probably decided "we need everybody". From there it probably devolved into who is in charge, how many people do we have and where, how many armed suspects and how many hostages, etc. It doesn't take 3 hours to come up with armored vehicles and a couple of tac-teams. My guess, is they were trying to figure out what the hell was going on. All the witnesses were probably drunk and unreliable, leaving them no choice but to proceed with great caution.
I'm sure it will all come out in the wash, and a few lower level officers will get blamed, probably who ever was telling other to take cover. Bottom line, that's a shit sandwich to be dealing with at 0200 hours, probably after working a regular shift. Probably standing there with a pistol an a couple magazines, no rifle or plate carrier in the car, and some asshole lights you up with AK/AR. All while a bunch of feminine dudes are running around screaming help my boyfriend and OMG type shit. Fucking WTF overload!!!
I feel for that cop...