Could you post some screenshots from the regraded scene with Rey handing Luke the saber? I need to end up marching that footage with the overcast colors from TFA and this sounds like something along those lines.
After the blanket yellow tint is removed from The Last Jedi, it doesn’t look overcast like it did when they shot the scene in The Force Awakens so its unlikely to help in terms of maintaining continuety. I’m pretty certain they reshot the scene again for The Last Jedi and the lighting conditions seem to have been pretty different.
Here’s a screencap comparison between the blu-ray and this regrade from that scene: