They uniformly cite slavery as the overriding cause of the schism.
Your big --aha!-- that the ordinances don't mention slavery is just do much doodle.
Walt
Misspoke? Try arguing to no end that you were "right" when everything told you that you were wrong, and doing it just for the sake of arguing.
All the so-called seceded states did have ordinances or documents of secession. Only 4 of the first 7 followed up with declarations of cause.
Your implications from those four documents is a half truth. Not one of those 4 declarations out of 11 confederate states was an official act of statute. They were nonbinding legislative resolutions stating the opinions of the persons who signed them.
The real statutory documents, the secession ordinances, do not say a word about slavery beyond geographical references.