HI there..
I think the first thing you should do if find out if they are really are who they say they are ie it could just be a phishing attack on you.
Which browser do you use if it is firefox download Copyright Infringement Finder click on the right image and check it,that often does give the right places where the image has come from ...not always but most times it worked for me
Also the thing is by taking images off the internet you can more than often find yourself in this position as you may find they do need a license .
Getty and a lot of places have scrapers that go around looking for images being used illegally that is why you may well have been found out ,although the best thing would be to just remove them for now to be on the safe side ... I don't know if changing the image slightly makes it yours but might be worth looking into