2573169 - SAINT Uninstallation: "Objects used outside the Add-On" error in phase CHECK_USAGE

While trying to uninstall an add-on via SAINT, you receive the following message during phase CHECK_USAGE:

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The process was interrupted, because an error occurred during the phase CHECK_USAGE, which requires a manual invervention.
The objects listed below are used by other objects outside the add-on.
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Checking the table displayed by SAINT, you can see that the "Using objects" column contains Z objects.

•  SAINT

delete, import, skip, fix, TN_PROCESS023, CHECK_USAGE, SAINT, SUPDOE, The objects listed below are used by other objects outside the add-on. That's why, their deletion may cause errors or data loss , KBA , BC-UPG-OCS-SPA , Support package tools for ABAP , BC-UPG-ADDON , Upgrade Add-On Components , Problem