Hi,
Unfortunately, it cannot be achieved by my testing.
My idea is to unlink the Quick Campaign from the Marketing List after the Quick Campaign status has been changed to Completed.
By now, I have tried to achieve it with Workflow, which cannot target at Quick Campaign at all,

Flow, which shows have unrelated the two records already but haven’t done in fact,

And JavaScript, but the field of the Marketing List cannot be unlocked or edit.

Also, the status of the quick campaign cannot be edit in the above ways. So the record cannot be reserved separately.
If this helped you, I'd appreciate it if you'd mark this as a Verified Answer, which may in turn help others as well.
Best Regards,
Nya