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Nah A LOT of pokemon that are RNG's have Dates like that. And if anyone accuses you anywhere tell them to run a legal.exe hack check. It will be legit. Everyone on smogon already knows it is legit ^^
Mattj is one of the most generous guys on smogon. He RNGs a bunch of sweet pokes and puts them as fully redis so everyone can get a copy. I'll send one your way later on- my wifi is acting up and being lame and won't let me connect =(
RNGed pokes are perfectly legal (like, event wise). That's actually how that Ditto you have now is flawless- an RNG catch. Other sites like serebii don't support RNGing as much. People here will trade for only the best pokes, so you actually DO want to breed for flawless ones. =)