Yes he met/hatch date (barring a few circumstances) aren't any real indication of legality. I mean, sometimes you have to go a hundred years in the future for some RNG's. Even non-RNG'd captures have that sometimes when people are lazy as hell and just leave the factory settings on DS or change the time for in-game events.
i see, thank you for the answerDate is completely irrelevant, since you can easily change the clock on your DS.