I have no idea why they did not charge him with resisting with force because he was. I have no idea why they charged him with cursing the cops as that is not even illegal in Florida.
I think originally they arrested him for underage drinking and lying about his age. I noticed last week that cops in Panama City Beach have made a thousand arrests for underage drinking so it happens.
Without an Assault or Resisting Arrest charge, the cops are going to have tough time explaining their actions.