I took a video levels HLG (with Rec.2020) test clip, converted this clip to V-Log/V-gamut and saved the converted video using data levels.
Comparing the original clip and the converted clip using YRGB Color Managed Science with the proper conversions gave a satisfactory result, however under ACES there was a noticeable shift, predominately in the shadows. Also as an effect of these changed levels some noise shows up as saturated pixels
Unless I made a mistake something does not add up, it could be Resolve or some ACES definitions.
For a shift in the levels see here: https://forum.blackmagicdesign.com/viewtopic.php?f=21&t=79972