Even among REs, the formation of the universe and earth are not totally known, proven and agreed, as this is tough to prove for obvious reasons.
I don't see the difference between FE and RE on the natural process vs supernatural being creation. Either could be either. Of course, with FE, you do have physics problems such as space shuttle and ISS can do experiments in 0g where things let loose tend to attract each other into balls, and when you look at other planets and the moon and the sun, they are round, seemingly spheroid, as the physics predicts round. You would need an explanation as to why it is flat. In RE, the explanation for why it is round is consistent with the physics, the experiments, and observations of other planets.
Also, you have to explain gravity again, because on a disk, you would be pulled to the center of the disk, not straight down. So you will need a lot of math and experiments. If you produce them, you will be rich and famous and go down in history alongside Newton, Copernicus and Einstein.