Both my x and I have independently obtained routine medical care and I have made many medical decisions regarding our children with no questions asked about custodial status. I just signed my daughter up for a driving permit, as I did for my son before, and I have the right as a parent to remove those lisences, WITHOUT showing my court orders. I also am unquestioned on school decisions. I haven't filed any lawsuits, but either parent may do that too.
I know that a municipality in New England recently had a law that restricted NCP access to school records. I use the past tense "had" because the state Supreme Court struck it down.
Unless a court order specifically restricts parental rights, all FLDad needs is joint legal custody to have all the parental decision-making rights he needs.
Another thought, though I am reluctant to go there: He can agree to this to firmly establish the child's residence, then if there are ANY problems later, he can file to change the status, and there is no chance on earth that he would lose. Time is on his side.
I do think he should get a bit more vacation time with his child in the Sunshine State, though. 100 days is a bit much across country.