Hi Mike,
Glad to hear you are back up and running here. Im still looking into wether or not there is a way to disconnect MailChimp from our end. I suspect that even if we could force disconnect on our end, you might still run into troubles if MailChimp is still pointing your old account to Method when attempting to connect a new one. We run into similar issues when connecting a QuickBooks Online account to Method. For example, when one user in QBO has the method App (pointing to a pre-existing Method account), and then another QuickBooks Online user in the same account attempts to connect a new Method Account. Obviously the New Method Account would have no reference to any existing Quickbooks accounts, but because QuickBooks still has that connection made, we run into authentication issues.
Ill report back with any new information I find.
Thanks Mike.
-Ben