Does Stab: The Musical exist? We don't think so, but we don't know for sure. The title “Wrongly Accused: The Musical” first appeared on promo artwork for Scream VI, but there was no mention of the musical in the film. 

But then, another exclusive poster for Scream VI came out and this one featured Stab: The Musical! StabMovies.com has been working a musical version of Stab for years, which is still in the development process, so it may be a reality one day!