I am also frustrated and bewildered why they can't release the name and picture of the "person of interest" so he can be outed, and why it took them 3 days to announce this was a homicide. Maybe I'm giving the police too much credit, but I have to believe there is a reason for this. Could it be that they've known all along who this individual is and just don't want to spook him? That they have had him under surveillance the whole time and waiting for him to make a "move", like trying to hock cue sticks, or something like that so they can get a search warrant, and build a stronger case against the guy? After all, all they have against him is circumstantial evidence that he was in fact with Mike when they left the pool hall. Of course to most, including me, the circumstances make it clear that this person is the culprit. Maybe they are just taking their time to build a stronger case against him. If they arrest him prematurely he may "lawyer up", and they'll get nothing else. Maybe I'm wrong and I've just read too many true crime books, or watched too many detective shows on TV, but I have to believe the cops are on this guy and he will be in custody soon.
You are probably right IF THEY HAVE BEEN IN CONTACT with the person of interest or had him under surveillance. They are probably doing what good police do, building a case or eliminating persons of interest.
JoeyA