So what you are saying appears to be that State secession was completely Constitutional, but these folks screwed up the paper work.
Congratulations.
You know the answer. At least be honest about it.
I will be completely honest about it - perhaps you should consider that position as well:
...the principle on which all our political systems are founded, which is, that the people have in all cases, a right to determine how they will be governed.
William Rawle, 1829
Screwed up? They ignored the un constitutional ad-hoc procedure that they themselves created out of whole cloth. By their own "standards," they were in violation of the constitution.
...the principle on which all our political systems are founded, which is, that the people have in all cases, a right to determine how they will be governed. -- William Rawle, 1829
Which people?