I think it is less likely, but I would have to read up on it more. My recollection is that there were elements agitating to leave for years before.
But again, it doesn't matter why they wanted to leave. People have a right to self determination. Having a bad reason for wanting independence is not justification for denying them their rights.
It's like policing speech. Arguing that only people who say the "right" speech can have "freedom of speech" is missing the point. The right exists for "bad" speech too.
The right to independence also applies to "bad" reasons for wanting independence.
“People have a right to self determination. Having a bad reason for wanting independence is not justification for denying them their rights.”
So a massive slave insurrection in the deep south could be justified on those principles.