My bet is the guy they apprehended was playing decoy to give the perp time to slip away.
The only thing out of his mouth was “I have the right to remain silent.”
Sounds like a plan, to me.
The police should keep that SOB in custody for as long as they can possibly do so. In this case, I would not mind if the feds got in on the matter as well, so that if he is released from local custody, he will go right into FBI custody. This guy‘s bank accounts need to be examined with fine tooth comb for the last six months, as to those of anyone in his family, and his house needs to be searched, as to all of his communications and computers. Because it seems to me that you are correct, that he was at least tangentially involved - his behavior was just a bit too suspicious for this to be just a coincidence.
Cui bono? Who benefited from this? That’s the real question here, and that is what must be investigated with the full resources of the federal government.