A CashPointClosing with status ERROR is not included in DSFinV-K exports by design.
Deleting a CashPointClosing only changes its status to DELETED, which is used to explicitly exclude entries from exports. Since a CashPointClosing in status ERROR is already ignored, deleting it would have no additional effect and is therefore not supported.
A CashPointClosing in status ERROR can still be retrieved via the retrieveCashPointClosing endpoint.