PJ, I do think he has a path to secure the nomination if it plays out a certain way.
As long as he is behind DeSantis for second place Trump won't spend a lot of time on him. He can just kind of hang around there using DeSantis as a human shield and wait to see if multiple indictments cripple Trump.
If Trump can't continue, the MAGAs will be looking for an alternative. It won't be DeSantis because the MAGAs see him as a traitor and he's already been thoroughly humiliated and emasculated by Trump. I think most MAGAs would see Christie as a big enough asshole to carry the MAGA banner and the establishment Republicans would welcome him as someone that is sane but still could turn the MAGA base out