LET THIS BE A LESSON TO ME
"Original Pre-made covers" they said.
What they _didn't_ say was that the "premade" part was on Shutterstock and you can find the damn image all over the internet, including on another Kindle book obviously being sold.
So... well, I feel dumb. But at least I figured it out before I published with the cover.
Now to find a Plan B
Yes, all in all it's a lot less messy finding out now instead of later. :-/