Historical CDO records not visible in reports due to absence from the contacts table

Hello,

At Eloqua, we have historical CDOs to store records that should not be in the online CDOs because they have completed their program flow.

At OIC, we have a contact table deletion integration to ensure that contacts do not exceed a certain number. Contacts are deleted 3 months after they entered the historical CDO and are no longer present in any of the online CDOs.

In reports, these records do not appear because they have been deleted from the contacts table and are no longer mapped to the CDO.

Is there a way to display these historical CDO records in reports even if they are not in the contacts table and are not mapped to the CDO?