A couple of points to consider. Both cameras have been exposed for 400ISO, with the grey card used to set a consistent exposure across the test. And the C500ii has been exposed half a stop darker than the FX9 to achieve that.
Curious where the iso 400 info comes from(hopefully not that 400 on the chart, which is the light level in foot/candles). All the other tests (lighting) were conducted at 800 iso (as this is the native iso of all the cameras) , but with the exposure up 1stop from normal..as the test was looking at the response to various lights, and it’s common to expose these cameras in this fashion as a compromise between noise and DR.
The fx9/c500 test is an over/under, and you would assume the test would be conducted at native iso— 800. Relative to exposure, both cameras were shot identically, however the fx9s control patch read in resolve to be 1/2 stop slower, so the zero point on that camera was adjusted 1/2 stop brighter. They’ve been rolling out data regarding the tests over the last couple of days, but other than lens and lighting info, I haven’t seen anything regarding camera settings for this particular test.