At COCA (I'm using it as it allows detection of the period), out of 143 sentences starting with
"Except the"
only 2 are ACAD (academic), the rest are FICT (fiction) to a large majority.
Thus I consider it as something frowned at in formal writing, and in fact I'd use "Except for the" for the sentence at the top of your posting.
But "Except the" is certainly out there with the meaning of "Except for the."