When we first created our criteria based sharing rules from SFDC to Marketo, we didn't share "Disqualified" leads as a Lead Status with Marketo. If a record is created through Marketo with an "Open" lead status that is subsequently changed to "Disqualified" by our Sales Team within SFDC, does that mean the record disappears from Marketo? I'm hoping that's not the case since many of our own employees want to receive our prospecting emails, but they should all be disqualified leads in the system. Please let me know your thoughts when you have a moment!
There should not be any automatic removal or deletion of your records in Marketo based on the status changing (unless you build a rule to delete them). What I interpret this to mean is that a record created in SFDC with a status = Disqualified will not be synced to Marketo (created or updates passed). So again, my understanding of this is that this restriction keeps records with that status from being created in Marketo (if they don't exist) or from syncing data from SFDC to Marketo (with that status).
If you're really concerned, it never hurts to test a record and monitor the behavior between they systems.