It was him, and here’s why:
While at PAX he (Patrick Weekes) was interviewed by a fan. Yeah, fan is vague, but Weekes confirmed the interview happened on his twitter account, and while he claimed some of the answers the fan attributed to him had a negative spin he never denied the following:
(Mr. Weekes dropped a lot of hints that he really didn’t like the ending. He also said something that was almost 100% verbatim from the Penny Arcade Forum post often attributed to him
Then there is this:
But here’s where the “huge amount of controversy” comes in: the writer, knowing the amount of trouble his statements would cause, deleted his posts and requested that nobody attribute his statements to his name, asking them to simply say “I heard” or “I bet”. These posts were also taken down by Penny Arcade at the behest of the author (well-known in the forums as Takyris), though Gameranx both published the writer’s name (Patrick Weekes) and received an anonymous screenshot of the posts in question, dated March 11.
Takyris is an account that has been on the forums since ME1, linked to Weekes’ LiveJournal where he discusses his work, and Penny Arcade users noted that he would sometimes bounce light ideas off of them. Some of the posts referencing what Takyris said are also still up, like this one (imgur), and this one (imgur), also from March 11, thereby making it clear that Takyris is the source of the denunciation and later redaction. One of the posts states:
So, whether he denied it after the fact or not, he said the same thing on multiple occasions. In the case of that PA post, and others, he said it from the account he’s been using since ME1 and had used the account to talk about his work and bounce ideas of members on previous occasions. That was 100%, no doubt it, indisputably Patrick Weeke’s PA account.
Here’s the actual posts where he realized he might have fucked up and starts worrying about his job:
The reason why everyone started crying, “imitation” after the fact is because people from other forums copied his words and it spread. In fact there are posts from people pissed off that he was “outed” and left the PA community.
The only reason people are saying it’s fake is so that [Takyris], a genuinely nice dude who just wanted to give some of his friends some insight on why the ending turned out how it did, won’t get fucking FIRED because you decided to fucking call him out by name you absolute pile of fuck juice and human compost
The Scarab already mentioned that people at Something Awful and other places read the forums and copy/pasted his posts at their shitholes weeks ago . and it was around that time that taky left. it makes me sad and I’m angry at the fuckers who took advantage of his trust in us.
So we know it was his account (that’s a fact), he said the same things on the PA forum that he said to someone at PAX, and the people at PA knew who he was and who they were talking to in that thread when he was posting.
There is enough evidence it was him that a jury of his peers would convict him of making those posts. If you want to let him, and Bioware, off the hook because they later claimed different, feel free. I understand completely why he would lie to Casey Hudson and say he didn’t write it, but this is far more that a mere he said/she said.