Seems likely it was David Dobkin:
https://www.reddit.com/r/Vive/comments/5q5rf2/software_exper...
https://www.elys.com/people/david-dobkin

Following up on other posters' comments (thank you!), while Carmack proposed Abstract Syntax Trees based copyright detection, he didn't seem to appreciate the standard court methods for detecting non-syntactical copyright violation for code, the abstract filtration comparison test (https://en.wikipedia.org/wiki/Abstraction-Filtration-Compari...). Dobkin it seems didn't have to rule based on his own opinion or based on some academic method whether there was copying, but whether -- given the very specific method laid out by legal precedent to know whether there was copying, assuming that method was true -- whether when he applied it, it indicated there was copying. That makes a lot more sense to me. Dobkin would be a perfectly suitable expert for doing that sort of test.

I am a bit surprised Carmack didn't seem to recognize this basic point. But perhaps I am missing further subtleties. Or perhaps he is just trying to indirectly shift blame to Dobkin when it really belongs to the legal system (or where actually the legal system correctly discerned something was going on).

For the actual 90-page Zenimax ruling which describes the abstract filtration comparison test in the words seemingly given to the jury for this particular case, see pages 21 onward (but especially page 26-30)
https://www.scribd.com/document/338147994/Ruling-in-Zenimax-...

For direct copyright infringement, only Oculus was found guilty (ZeniMax claims post-trial at http://uploadvr.com/zenimax-responds-john-carmacks-facebook-... some employee admitted he copy-pasted some code to an Oculus SDK.) Carmack was innocent.

For vicarious copyright infringement (ie management should have known/prevented it, https://en.wikipedia.org/wiki/Vicarious_liability), Oculus/Facebook/Carmack were innocent but Palmer Lucky and Brenden Iribe (before they founded Oculus?) were guilty.

For contributory copyright infringement (https://en.wikipedia.org/wiki/Contributory_liability, a "party materially contributes to, facilitates, induces, or is otherwise responsible for directly infringing acts carried out by another party." ), Oculus/Facebook were innocent but Iribe, Palmer, and this time Carmack were guilty.

BUT, the ruling then goes on to say that "the defenses of license or de minimis use bars Zenimax's claim for copyright infringement" for Palmer, Iribe and Carmack (but not for Oculus). So whatever Palmer/Iribe/Carmack did wasn't that bad, but the actual copying of code to the SDK by Oculus somehow merited $50m damages (I can't see why that won't get reduced substantially on appeal, no copy-pasted-code-to-an-SDK really caused Zenimax $50m damages.)

For violating the NDA Palmer Lucky signed before Oculus was even formed (but which was ruled to still be in effect after Oculus), Zenimax gets $200 million.

And for "false designation of origin", (https://en.wikipedia.org/wiki/False_designation_of_origin), where the manufacturer/seller lies about the origin of their products, Oculus was guilty for $50m, Palmer Lucky (the visionary founder) for $50m and Brendan Iribe (the CEO) for $150m. I'm not sure I understand the factual basis of what happened here, but having been in startups that deliberately obscured the origins/key parts of underlying technologies to angel investors, I can see the origins of product misrepresentations as being worthy of substantial damages as it really does affect Oculus's value and Zenimax's ability to be compensated for "their part". Probably will get knocked down too, but this is the most defensible part of the $ amount.

Sorry for the long post.