This petition alone in under 24 hours has reached 100 signatures, and Niantic's original post has now reached 600 comments, with yet, no response or statement from Niantic has been seen, and, since posting this petition, Niantic has posted an unrelated tweet. We will not let them try to cover up this PR mistake, and make them issue both their autistic players, and the Pokemon GO community, an apology and reconsider the event.
@artfulretro on Twitter has found out that this event is not just asking people to attend the AS walk, but Niantic is providing a full event space with Pokemon go-related activities.
Additionally, we now know Niantic's PR company is TriplePoint - who may be responsible for this, led by @andrewkarl - may be worth a shot tagging him in this.
On other sites, a discussion on r/thesilphroad, a pokemon go reddit community, has been posted asking for support. A tumblr post, with currently 2,000 likes and reblogs, has also been posted. So it seems news of this is spreading beyond Twitter, which i'm very glad about.
And lastly, i'd like to thank this community for pushing forward to try and get Niantic to see the error of their ways. Keep going strong and posting, and know we won't let them let this go. #SupportAutisticPokemonTrainers