So I would guess, the break up happened after the overrun.
Yes. The tyre tracks gradually run off the centre of the runway to the right and then pass across the grass to the localiser. Where the aircraft passed through that, the tracks end as the gears collapsed. The subsequent aircraft fuselage track indicates a stop in very short order. Thus, it appears that the aircraft broke apart as it came to a stop with the gears collapsed, as the rear end tried to overtake the nose, which was digging in hard at that point.