Images displaying third-party ownership or branding not deleted - Wagon Train

According to the image guide (https://help.imdb.com/article/contribution/images-videos/image-guidelines/G27LPBQZA7EAZGJW?ref_=helpms_helpart_inline#) "Images displaying third-party ownership or branding, such as watermarks." are not allowed.* For that reason, I tried to delete several photos of Wagon Train, such as this one: https://www.imdb.com/title/tt0050073/mediaviewer/rm1756636416/, but my contributions were declined. Was this in error or does IMDb have a different idea of third-party ownership and/or branding than I do? These are the submissions: #250730-162348-520402 #250730-162358-520602 #250730-162407-090502 #250730-162416-582102 #250730-162425-688002 #250730-162434-557202 #250730-162444-139002 #250730-162453-171702 #250730-162502-458402 #250730-162510-410902 *all pictures had a watermark from tv channel Starz, which started in 1994, while Wagon Train is a 1950's-1960's series, a fact I pointed out in all contributions.