I have noticed that TynEye does not, and cannot caught all the fake pictures that populated some many ads...

To locate fake ads, you need to work with phone search complementing TynEye research of pictures, and email research plus some google trick like the search in the 'cached mode' to grasp details that might help to figure out changes made in the ads.

TynEye is just a new tool: exclusive reliance on it can direct you to the wrong directions.
BM