Which country do you live in? If you don't live in the US or the UK then probably we can ignore what the tech guys/engineers say. Based on my own experience, they are usually clueless about these issues. If you can, argue with him on how this is working as intended when it clearly isn't. Let's hear what he has to say.I don't know if we'll ever get a fix to the near black gamma shift when Gsync is on. I had an LG tech over to try to diagnose my TV and he said he had to follow up with the engineers. He called me later the same day and said it's basically working as intended.
HDTVTest says that this is because the dithering fix is disabled in VRR which causes the brightening at 8:40 in this video:
I hope that LG can patch this in a firmware update. It is terrible looking and extremely distracting.
On the side note, I'm pretty sure LG is now aware of the issue but yeah there's no guarantee LG will fix it. Recent update fixes the long standing issue of pulsating oval shape in game mode though so it gives me a bit of hope.