Use SuiteScript to Cancel a Vendor Bill

I have a user event script that copies data from a vendor bill into a new transaction, and at the end, we want to Cancel the Vendor Bill.  Void does not work because of the accounting preferences, and because the Bill is in Pending Approval status and is never approved.  Does anyone know if there is a method to do this?  Setting the status field with script does not work.  I can change the Approval Status field to Rejected, but that doesn't actually cancel the Vendor Bill.  Help with the syntax to do this would be greatly appreciated.