What you have posted is a total of 4 states Immediate causes. That means right then right there. This is not half of the Confederacy yet you use this to try and prove your "We the Slave-holding States, do join with our sister Slave-holding States, to create a Southern Confederacy of Slave-holding States" etc. etc. Note that I came back and posted the Ordinances of Secession which are more states and also included statements by your 4 states.
You fail miserably to prove your statement, just as you fail to prove the CSA leadership refused to arm the salves simply for the sake of maintaining slavery, just as you fail to prove blacks did not serve the CSA in any serious number, in short just as you fail to prove the issue(s) was all about slavery.
I am gone until this evening.
Have a Dixie day.
GP