The white rabbit meaning is obvious!
Hoskins specifically asks for a white rabbit in the pet store,
Alice follows a mysterious white rabbit into "wonderland".
Hoskins wants back in the game, so he brings the white rabbit to mortwell,
to signify he want's back in the rabbit hole that mortwell controls,
and that he feels he owes him, but shows he is not really mad at mortwell,
but wants things back the way that they were before his incarceration.
Specifically bringing the rabbit shows his loyalty while in prison and present.
By saying this is the path that feels right to him, and the white rabbit
brought him back there. Which he obviously had plenty of time to think on,
what his future will be, while in prison.