Thank you for your reply!
My graphics card is up to date.
I have printed this photo before, only with the watermark, and it appears the same way as it does on my monitor (or close enough, certainly not green) so it's not the monitor.
I made the changes to lightroom and photoshop that you recommended and the photo still saves the same way (green in some programs, normal in others). I reset everything (programs, computer) after making these changes. Here is my test photo:
Still looks completely normal as a background... side by side.
And this is the test image itself, straight from my computer to this forum and not screenshotted like the others. The colors are normal.
And for fun I decided to try on another photo upload print site, and the color is distorted again.
And just to be absolutely sure, I deleted every photo in lightroom, reimported everything with a blank slate with the new settings, did it AGAIN, and same results.