He's been clear that he's not Asahi Lina... and he's also not a GPU hacker as far as I know.
He even did a super-cringe "take over" video, where Asahi Lina "broke into" one of streams: https://www.youtube.com/watch?v=effHrj0qmwk
I have no specific knowledge, but it seems very clear to me that at the very least marcan is a collaborator in the persona of Asahi Lina; and absent further contrary evidence, them being the same makes sense.
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¹ And if stream key exfiltration actually happened, I find it hard to imagine anything but acrimony arising.