The lawsuit against the police will go no where. There are at least 5 SCOTUS decisions (maybe 7?) that say the police have no duty to protect anybody. Period. Suing the police, regardless of their failure to perform under any conditions, is a non starter. See: So You Think The Police Are Bound To Protect YOU , third paragraph. His lawyer should know better than to do this.
The cases where SCOTUS made this ruling are way worse than this one. This one will go noplace.
The way the justice system is set up is actually quite simple: The general public act as bait. If a criminal takes the bait the police have a duty to investigate and attempt to apprehend the predator as a matter of general public safety, but they don't have a duty to protect any specific individual from harm. This is exactly why the second amendment is in place to protect our right to defend ourselves from harm. With out the right to defend ourselves there is no provision for personal protection anyplace under the law.