They never actually hit Absolute Zero. They got damn close though.
As for they speed of light thing. Never atrifically created. It happen in almost unmeasurable amount of time, like a very fraction of a second. Only near black holes. That's how they find them, by radiation that flips off of light beams, at that instant it comes off, it is barely faster then light, but long enough to get away from the gravity. Or else we wouldn't know the exist we can oly measure Radiation given off by them. That's why tehy collapse, eventually they radiate off all there mass.