Business Central Couple Has Not Synced CRM Account - Business Central Customers

I already have a CRM Account with customers and would like to associate those CRM Accounts with newly created Customers in Business Central. I've set up several businesses that all use the same CRM system. I'd like to link a CRM Account record that wasn't created in Business Central Customer to a newly created Customer record in Business Central. However, when I try to configure coupling, the Common Data Service only contains CRM records that have been synced with Business Central. (Created in CRM from Customer records in Business Central)

With the Common Data Service Connection Setup, CRM Account records are created in Business Central. After the synchronization, new Business Central customers are created, and I connect to CRM accounts that are also created after the synchronization.