You killed the thread with an answer that made complete sense. I was hoping there would be page upon page of heated discussion and deep consideration.
However, I will continue on a slightly different tangent - many Round Earthers think the Earth comes between the Sun and Moon causing the Lunar Phases, which, if not completely absurd, would prove geocentricism.
However even if the angle explanation were 100% correct, it would by no means rule out the Flat-Earth/Round-Sun-and-Moon model.
Furthermore, the Flat bodies scenario remains not disproven on the grounds of the various Lunar phase explanations which can be provided for said scenario.