To contextualize Retartist's response, here are relevant diffs:
Retartist's placement of TRPoD's reversion in evidence immediately after the vandalism accusation: [1]. Retartist identified the quote as an "attack quote."
When TRPoD returned the full quote again, Retartist removed the quote, saying its only purpose was to attack: [2].
Retartist noticed a talk page bit about the quote, and stated that he didn't realize it was sarcasm, though he is doubtful of that: [3].
Retartist's retraction of the evidence: [4]. Reason given: "stupid quote was a 'JOKE'"
Overall, there is some evidence to support his reply.
As mentioned in his statement, he initially planned/attempted to act on behalf of 8channers/recruit 8channers as investigators in this case. The work was initially on-wiki, but was moved away on Nov. 10th after complaints: [5]. To his credit, he has clearly not ended up acting as a proxy for or heavily using 8channers, and evidence is evidence no matter who brings it.
Fearmongering about Gamergate target Silverstring Media: [6]. Retartist had no basis for the fearmongering: [7].
As a side note: I am aware that there have been concerns given about Retartist's attempts to start dispute resolution processes. While I see no problem with them (trying to calm matters down is good), I think it is best to clearly put them on record. Retartist started a request for mediation and a dispute resolution noticeboard section (now located here).