Any lawyers or people familiar with law want to chime in on how this will turn out?
The officers in question have no duty to identify nor use police marked vehicles (note their uniform DOES say POLICE on it).
As long as the officers present the suspects in court with convincing evidence that they were personally involved, they're going to federal prison.
source: Best friend is a federal officer.
tldr: Do not try to burn down a Federal Courthouse. You will not pass Go. You will not collect $200.