It's starting to look like neither state is going to get a do-over. The next step will be taken by the credentials committee of the national convention. They will decide whether or not to seat MI and FL's delegations. The credentials committee will be controlled by the likely nominee. Both candidates are not stupid. Both candidates realize that not seating the delegations would not look good to some people when November comes around. Therefore, there is a high likelihood that the delegations will be seated in some form. Maybe they only get half voting power or maybe there is some kind of other compromise that can be made.

The fact remains, though, that the determination now is going to be up to the credentials committee (and by extension, the candidate) and that there is nothing to be done at this point until such time as the committee is seated. IIRC, that's June -- someone correct me if I'm wrong.