Jetpack would have had no way to delete the header image, so I'm not sure what happened there.
As for the other issues with the Tiled Gallery, I suspect it has to do with the speed of your site. Your site is loading extremely slowly for me. If you have Photon activated, we get the images from your site first, before we are able to serve them to your site's visitors using Photon. If it takes longer than 10 seconds to get the image from your site (ie, the connection times out for that image), then we won't have it on our servers and won't be able to send it to your visitors. I do not know why your site is loading slowly, though; you might want to speak with your host about that.