“The next day, detectives re-enacted the shooting with Zimmerman at the scene. “
http://www.cbsnews.com/8301-201_162-57406183/video-shows-zimmerman-without-obvious-injuries/
So Zimmerman submitted to hours of interrogation on the 26/27th, then came back to do a walk through - that's the way I read the report.
A sure sign of guilty conscience.