My pixel 3 had the same problem too after I changed it's battery.
I didn't use isopropyl alcohol, but alcohol. I don't know if it's the reason of the green lines, but I think maybe it's because I accidently pulled the display connector out when I tried to pry the battery out from the right edge which should be from the left edge only according to the guide, and although I've pushed the connector back after that, it's loosened.
[image|3129231]
(the part in the red frame is the display connector)
So I removed the wireless charging coil again and pushed the display connector for many times carefully, especially on the right side and then the green lines disappeared.
My pixel 3 had the same problem too after I changed it's battery.
I didn't use isopropyl alcohol, but alcohol. I don't know if it's the reason of the green lines, but I think maybe it's because I accidently pulled the display connector out when I tried to pry the battery out from the right edge which should be from the left edge only according to the guide, and although I've pushed the connector back after that, it's loosened.
[image|3129231]
(the part in the red frame is the display connector)
So I removed the wireless charging coil again and pushed the display connector for many times carefully, especially on the right side and then the green lines disappeared.
Hope this experience is useful to other users.