Thanks for the reply, change-refuse,

One reflection is light-based, and the other one is Image-based, while the image-based (environment) kicks in when it would be otherwise black.

Here is how to explore it. Set up an ACEScg 32-bit float image in Photoshop. Create a portion in 0.17, another 0.5, then 1.0, and the last patch in 1.75 (here, each time, all three channels are the same (RGB), save as Open EXR, load it into the Dome light, and set it to ACESCG. Then, place a sphere above your Torus "slice" with the same material.

Measure the Values with the PIXEL options in the RS Render View. I can't see here a lot of differences.

For quality control, I would avoid any 3rd party HDRI, especially Radiance (".hdr"). At the same time, some OpenEXR hdri holds just Radiance material, which will not help to make a bad source better.

The Test pattern that I described above will give you certainty.

Cheers