The domains belonging to the REDDCRYPT organisation that are configured as trusted in the REDDCRYPT portal are listed here (https://app.reddcrypt.com/settings/organization/trusted-domains via TXT DNS Record in the REDDCRYPT portal under Settings -> My Organisation -> My Domains).
With 2034 SP2, you can also specify whether the REDDCRYPT implementation creates new accounts in the REDDCRYPT portal via the appliance if they do not yet exist.