Trump was not fleeing from justice when he came to Florida.
The extradition clause applies to persons who have fled from justice.
My understanding is if someone is charged in another state that state can request extradition of the accused. They can’t just go in and take him. If the person goes voluntarily there is no need for extradition. But if that person doesn’t go the state can request extradition and the state can assist or reject. Governer destantis has chosen a side.