If a registrar doesn't meet its obligations, the SIDN will disbar a registrar. The result of this is that all domain names registered with the registrar, will be without registrar. The owners of the relevant domain names will be notified of this and are given the opportunity to host their domains with another registrar.
To transfer a domain name hosted with a debarred registrar, no transfer token (EPP code) is required. At the transfer page, you can enter 'notoken' after which the domain name will be transferred without token (if possible).