Excellent video and series!The 2GR engine was not deigned to work with a manual transmission so the Evora uses the stock flex plate with a bolted on flywheel and clutch plate. The shop manual calls the vestigial flexplate the "ring gear"- presumably Lotus did this because the flexplate has an outer ring gear that engages with the starter. The 400 has a lighter flywheel and I think you can fit that as a replacement for the earlier cars.
There is a great description of the development of the Evora transmission here:
I will be interested to hear more about what actually failed on your car- Lotus have revised the clutch/flywheel since the car was introduced which suggests that the original set up was less than optimal.