If you want to be real in your fantasy novel change the scene.
I think in no crime scene in the western hemisphere it will be possible for a non LEO /EMS / Firefighter to come that close to a victim of a crime after a hostage that she/he can tell the victim to jump into the care.
If you don't have done it, look one or two crime movies. In all and any there are the "Police Line - Do not cross" signs at the scenes of crimes. And don't try to cross them at a real scene - just a good tip!
But if you want your protagonist in your novel to do that - well, it's just fiction and no cent more. Do it!
Evenhand (Cop Movie): You can't be everybody's friend
There are two things I'm good in, the second is arresting people
I'm looking for Drug/Narcotic Unit patches together with DUI/DWI unit patches for a frame in our Anti-Drug-Team bureau
Also looking for Massachusetts Police and US Capitol City PD patches now!