Has anyone run into issues where a user associated to the Change order has been terminated?

Summary:

We're experiencing issues with a couple of our change orders. The original user assigned to the CO was change analyst who has a terminated account (no longer with the company) prior to the CO being completed. The new Change analyst tried to add new approvers and the users shows as listed for approval but the "Awaiting Approval" is missing under the Response.

The change analyst also loses the option to add or remove the user.

On a separate CO, an approval request isn't visible to an approver in his Worklist. When he searches the CO, he does have the option to approve. However, when he approves, it doesn't record the approval in the CO.