"Everything in the previous post is now dated information. Apparently I was using an SDK from 2019 (I thought it auto updated for some reason when I first upgraded 2 years ago -- woops). After plugging some values into the new SDK I was able to get eyes working with a third spine bone added. It has you plug the eye bones in manually now and you can seemingly set the max eye deflection for Left / Right / Up / Down angles individually. It seems I'll need to redo some experiments but at this point I may just rebuild a big part of the model from the ground up anyway so I suppose it's not that big of a deal.
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