The green tint is present on mine at low brightness but only at the bottom of the screen, I am aware that this is just about normal for AMOLED screens and it's way better than the Pixel 2 XLs P-OLED screen and it's blue shift that I actually just got used to.
More concerning is there is also a visible darker bar across the top in line with the selfie camera at these precise conditions as well - QHD+, 120Hz, brightness under 30% - I also run sRGB but this has no effect. In 99% of use this isn't noticeable, however I had already about screen issues and decided not to go look for them, but last night while in night mode and reading in low light I noticed the green patch.
I'm tempted to hold out a week or so to see what response OP has and then I'll be pushing for a replacement from JL. Sigh, why can't phones just be properly QCd before sending out?! I went through 4 Pixel 2 XLs before I got one with all the pixels working, I really don't want to go through that again as setting the phone up how I like it is just a big massive time sink!