I would make a wager that there is a 99% chance he didn't make it. If you look at the images from his twitter account, there are many images that he pulled from other web sites. Not one other image that he has posted is from imgflip. So why come and make only 1 image a month ago? Most likely it was something he saw elsewhere and posted that image on his twitter account, like maybe ifunny https://ifunny.co/tags/berniesanders/1452804097. Just because you can't find it under "Bernie Sanders WTF", that doesn't mean it was created privately. That image template has been recreated multiple times and can be found using a variety of different titles. It could have also been created by having it as an uploaded template without sharing the template for others to use, which means it wouldn't come up in any search. It could have also been deleted by the creator or imgflip for whatever reason, which would be another reason why it doesn't show up on a search. All I am saying is that I think you are jumping the gun in saying that it was Seth MacFarlane created it.
