He's tied to Rhythm Test and the Fever version of Night Walk for the Credits.
Hell, he's not even made cameos outside his own franchise like the Chorus Kids have (as evident as my last post).
The X/Y leaks were as early as February of 2013 but wouldn't be public until May 11 2013,
right before the English names for Pancham, Helioptile, Gogoat, and Fletchling would be known. And sure enough, they were all stated in the first batch of leaks (though with Pancham being "Panchum" as I stated).
Aside from that, the first batch of info from Sal's informant was "public" on June 10th (though Sal received the e-mail weeks prior). As evident on June 19th, Sakurai
had not decided on a Pokemon newcomer at that point in time.
http://www.nowgamer.com/news/1970393/pokemon_in_super_smash_bros_how_theyre_selected.html
The decision for Greninja wouldn't have happened until after October 11th of that year, when X/Y came out. Then, it would only be a matter of
weeks that Greninja would be the most popular Pokemon of Kalos thanks to the Protean Hidden Ability.
Sal's informant gave off the second batch of leaks on April 7th of this year, the day before Greninja was announced.
However, that doesn't mean the information the informant had was fresh. Considering the informant had info dating back to before E3 of last year, the informant could have been sitting on outdated info in regards to an X/Y Pokemon. Since again, it wouldn't have been decided to be Greninja until after X/Y's release.
This also goes back to the X/Y leaker, who gave
all the information he had to PokeBeach in February 2013, though only spurts of it would go public at a time months later.
See above; the X/Y Pokemon decision was much later than other characters. Unless you honestly believe that Sakurai back in late 2012/early 2013 decided upon Greninja, who was completely unknown to the public
and to him at the time?
Now, if the informant DID know it was Greninja prior to the second leak, there's
still the issue that GameFreak would be on his *** over leaking him, which you've seemed to ignore me saying. There is a substantially larger risk in leaking anything Pokemon related than any other of Nintendo's franchises. Enough of a risk that even sites like
Serebii were threatened with C&Ds during B/W's release and people who got early copies of X/Y were
forced to give them up.