Or do we judge this by a crooked nose? Which Zimmerman could have already had. Then how do they know it was broken by this incident?

Paramedics checked Zimmerman at the scene with no transport to the hospital. If he had a broken nose, they didn't go to the hospital for treatment or x-rays to determine the nose is broken. So they must have been minor injuries.

I haven't heard that they did anyway.

If it was just a casual conversation at the scene of the incident, there would just be notes taken by officers. That would be very unusual though, who can imagine anyone but Barney Fife conducting an investigation in such a way. Then again, this incident was bungled in every other way possible.

Maybe the feds have the tape if it ever existed. Even though, if he told the cops he was injured, they should have noted the visible evidence. A broken nose is easy to see.

His every moment from the time they went through the door is on audio & video.
I'm glad the feds have it, but it'll be awhile before we get to see and hear the evidence.