No two muslims doubt that the knowledge of Rasulullah (SAW) was greater than any other creation.... But if everything is simply "everything" which doesn't leave anything then that's simply false, because it implies that his knowledge was unlimited, and not even Barelwis (atleast in their polemical works) do not believe in this. But if that "everything" is somehow restricted then that is established and this is what Deobandis and Salafis believe. As for what are the exceptions with that "everything" and how that is restricted than that's a different issue.