I am not sure how this relates to what I posted, but as that article at least alludes to, the fact that he calls this all hypothetical is fairly irrelevant for a number of reasons: the accuracy of his description and consistency with any non-public information about the murder scene, inferences that a jury can make about what OJ is actually saying despite language to the contrary, and how this lines up with all the other terribly incriminating evidence we already know about.
What keeps OJ from being prosecuted for anything having to do with the murders again exist with or without this near-confession. Double-jeopardy stands in the way of another murder trial and alternative laws on the basis of which there could be federal prosecution (i.e. civil rights charges) are difficult to apply to the facts of the case.