Social networking sites are being increasingly subject to censorship of certain specific images that are contrary to their terms and conditions all of a sudden.
Avoid this problem by simply renaming the file or JPG of a poster image to something other than its default title.Or take a screenshot of it and upload that instead.
Call it anything you like as long as your title doesnt include any keywords that fit the description of the image you are uploading.
If you do this it means that the networking site has to manually look for and find your uploaded image amongst millions and millions of others instead of using a search filter to locate an easily recognisable filename to delete.
If they want to censor then dont make it easy for them.
Make them work for it.