I think if you look at how the committee finished up, UCF would still be behind the Big 3 (Oklahoma, Georgia, Ohio State for the last spot) even with a convincing win over Florida. My logic behind that is a 2-loss team was very much in the discussion late, so would the committee rank a 2 loss Georgia behind an undefeated UCF? It probably depends on the margin of victory in that UF v UCF game.
In my opinion, in this current format, the only way a G5 team gets in is they play a very tough OOC (no cupcakes) and they have another ranked team in the conference they get to face late in the year (ideally in a championship game) and they wax them. When UCF waxed a ranked Cincy team, they moved up 3 spots. And they would need craziness around them.