Currently it is not clear how the process of removing Sandboxes looks like:
Your documentation https://help.doit-intl.com/cloud-sandbox-management/create-gcp-sandbox-accounts does not give information about how Sandboxes should be removed.
Your support team confirmed that: "Even when removing [the sandbox project] from GCP, it will not be removed from the CMP list."
It should be possible to delete Sandbox projects again or at least the best practise should be clarified.
Please do not upload confidential information
Next, try drift hunters. Superb physics!
The write-up is sent to the quality assurance https://chinesebuffetnearmenow.net/ division for a second review after completion. The writing and proofreading crew puts in endless.
+1, also it would be nice if CMP detects that a project has been shutdown on GCP side and marks the Sandbox as inactive / deleted.
Imho, this could be a valid way to remove a sandbox.