Hi @Dawn Lowery ,
I ran a test against what you said.
When a terminated employee's OneDrive account is marked as a duplicate account and the primary site collection administrator is reassigned to an active employee, deleting the unlicensed OneDrive account of the terminated employee should not affect the active employee's OneDrive. The active employee's OneDrive is a separate account, and the deletion of the unlicensed account will not remove or impact the active account.
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