It's not a f2u base, if it was
1. doing a reverse image search would immediately bring up a huge number of the same thing recolored, however it does not.
2. The watermark would not be red, nor in the middle of the original art.
3. In the original art many features like the expression and side panels for the shoulders would not be colored in, they'd be blank or have straight black lines. This is how protogen bases generally work.
4. The image would not have existed standalone for so long, and the same version would not be posted in many different places.
What they mean by this is that they traced. There a HUGE difference from tracing a piece of art and using it as "a template" not to mention, if they did they would have added the permission they got from the original artist to do so.