crashfrog
Commenting on the link you posted, as you say the top level refers to "the London Museum". As a Londoner, I can categorically state that there is no such institution in London. The nearest (in name) is The Museum of London - dedicated to the history of London, and thus
very unlikely to be a repository of such an item. It seems to be typicl of such faked photos: credited to some distant organisation. It is noticable that in no case on that site are
exact locations given for any of the photographs, thus rendering all of them highly suspect, given the ease with which photographs can be manipulated (even leaving aside the possibility of physical fraud).