The fact that "Shakespeare" may not have written the plays in fact does indeed not do my argument any favors. But "Shakespeare", even if 'socially constructed', yet should be strictly confined to the words which we commonly call his, if we wish to use the reference with accuracy.
My argument remains, that if one wishes to call any film "Shakespeare's X", that it must have the words which we accept as Shakespeare's present within it, in such a way that a person with no familiarity with Shakespeare would apprehend those words that are considered to be Shakespeare's. This is uncontroversial - as anyone who would release a film entitled "Shakespeare's 'insert any name of Shakespeare play here' " would find, if she used NO WORDS AT ALL from Shakespeare's play in her dialogue. Using Shakespeare's words is so easily done with sound film that it's trivial: and it may be supplied by text intertitles in a silent film, or be indeed provided by live readers or by the post-production addition of the dialogue. But if the audience itself is asked to supply Shakespeare's words from memory, then that film (or indeed play, should a producer have the effrontery to produce a work of Shakespeare's, without using his words, and yet seek to retain the name of 'Shakespeare' on the marquee), whatever else may be said about it, is not Shakespeare's.
Shakespeare reduces to the words which he wrote: without the presence of those words, as appears to be the case with the 1912 silent "version" (judging from the clips I have linked to above), then it is NOT Shakespeare: it does not suffice to say, that I recall Shakespeare, whilst I watch; or that the film-maker claims that the actors seen were reciting the lines whilst filming and that you could if skilled lip-read along; or that the scenes convey the physical action of the play. Without the words, a shadow of Shakespeare, a ghost of Shakespeare: but no Shakespeare. If the audience cannot apprehend with their own senses the words used by Shakespeare, be they text or spoken, then the production may not be called "Shakespeare's", with accuracy.
Bodkins! Mayhap I have shaken my spear 'bout this point, too long.