No. You can't tell people to credit you for something you didn't draw. There's no such thing as getting credit for "rendering" aka erasing the background off someone's work.
FAQ #217:What are "Stock and Resources" and can I use them in my submissions? "Only the legal owner of an image or resource has the ability to offer the work for reuse and images taken from print or film, images of celebrities, models or manipulated "renders" are not considered valid stock or resources. Any website offering these materials is not regarded as a valid stock and resources site."
Unfortunately, your idea of "rendering" is completely and utterly wrong. You assume rendering means...this, but in fact, it actually means to apply shadow and texture or it applies to 3D models. The rendering you're doing is a stupid internet definition with no real artistic background; it's false. It's art theft believe it or not. So don't take this personally, but you will be reported for copyright infringement unless you have permission to actually edit these images.
FAQ #157: Can I use things created by other people in my submissions?
FAQ #217: What are "Stock and Resources" and can I use them in my submissions?
"Only the legal owner of an image or resource has the ability to offer the work for reuse and images taken from print or film, images of celebrities, models or manipulated "renders" are not considered valid stock or resources. Any website offering these materials is not regarded as a valid stock and resources site."