It doesn't really matter anyway as far as flare/float is concerned, if you haven't touched down by the inset marker lights it's a mandatory go-around.
No that is not the case.
If
during the approach it appears that the touchdown will be beyond the lights then you have to go-arround.
Having completed the approach, if the flare causes a float then it is 100% up to the crew if they go-arround or continue with the landing.
If you do make an approach at the correct speed round-out / close throttles and then float past the lights, you could try a balked landing.
But.
If you hit the bridge or any other obstacle on the way out, you can not claim that the airport authority required you to make that balked landing it is a 100% crew decision at that stage.
Remember also that in many cockpits the lights are not visible after a certain point in the landing even if you hit the aiming markers exactly.