Yes there is a difference in the documnets. abi Something like 9 to 4 give or take. Formal, legal, offical yes I can understand that Also the fact that slavery was not the only factor.
Now the rest of your post is just your opinion and BS I won't even bother responding to it.
From The Mississippi Cause of secession--
"It seeks not to elevate or to support the slave, but to destroy his present condition without providing a better."
Fact not my opinion.