Going way out on a limb to speculate here... suppose this does turn out to be the worst case scenario crime, and the POI is involved.
He's had 5 days of custody to get raked by LE, several of those apparently without legal counsel. Is he the type that would 'crack'?
We can look to his past misdeeds and misadventures for clues, and he actually seems kind of the opposite. We see repeated instances where he owns up to previous mistakes, confesses his mistakes, admits to nervous breakdowns, and so on. Whether all the things he's conceded are entirely true isn't necessarily the point, just that he's shown a lot of past tendency towards admitting things, as opposed to denial and self-delusion. Whether he was exclusively involved, assisted, or just knows or suspects something, past history suggests he'd be more inclined to talk than to clam up.