I think we need to think from perspective of shopping cart first.
If it is approved, and it is in transfer process; Means due to some reason, it has not been converted to PO.
So we need to change the status of shopping cart using /SAPSRM/* FM to in approval and again by using FM we need to make it approved.
If user has created new shopping cart for this, we can go by FM SWW_WI_ADMIN_CANCEL stated above.
But the same FM gets triggered while using option logically delete. You can try.