Is Ragol Earth?

[Forge]

Actually, there is no chance that DF could be sent to Earth, since the casket containing her originally came from Earth just before the destruction of the Earth.

Instead, the Alisa III (another spaceship) was sent through a warp to Earth, and this may have caused the ultimate destruction of Earth (PSIII - Aron's ending). Due to this, the Spaceship Noah was sent to Algol, and then eventually to Ragol.

And if you're suggesting that DF has the effect of changing the creatures of Ragol, then only the Dark creatures were affected/brought with Noah.

Now, the Dragons, this is more of an area for debate.

The Dragon (of which there are several, presumably) bursts up into the Central Dome, possibly from the Spaceship Noah, since Rico asks "Is this what destroyed the Central Dome? It looks like the remnants of some energy explosion." In PSII, dragons were a common enemy on the Spaceship Noah, so could these dragons have come from Noah?

The only drawback to this argument is that the Dragon in the Central Dome is in fact a wyvern since it had only four limbs. All dragons on Algol had six - two arms, two legs and two wings. (I'm not counting the tail as a limb.)