The site on the left is Gateway Pundit, which often posts false information. The editor of the site, Jim Hoft, has said he expects to get a spot in the White House press corps soon.
Hoft's post noted that the supposed butt pat "was not as apparent in the video" that he embedded in his story. Meaning he literally published information that debunked the fake while presenting the image as real. Hoft subsequently deleted his post, but it's still available in Google cache.
The photo was also picked up by a Nigerian news site, which went with the headline "See this picture of Obama putting his hand on Melania Trump’s 'bum bum' (photos)."
After promoting the fake image in its headline, the site ended its post by declaring that "a jobless person, took it upon his or herself to Photoshop the picture and placing his hand on her bum bum."