Just seems to be FUD with no basis for it, and even if it's true he had no access to Monero in any way at that time. There is no backdoor, everything is FOSS, and he wasn't even a maintainer at that point (he stepped down from all duties in 2019).

This source tweeter used GPT4 to confirm his "analysis" and revealed no new information, just seems like another normal hit job on Monero...

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