Can’t be fired, eh? Then pull the cards and garnish their wages until it’s all paid back. Make them now use their personal cards and submit expense reports for reimbursement.
When I was a typist for the Army Corps of Engineers, many years ago, the procedure was for every transaction to be examined before reimbursement was approved. Not anymore.
I believe the reasoning was that it cost less, in the big picture, to pay for people’s trips to Vegas and gym memberships than to employ regiments of “Voucher Examiners” in every agency.
This is the federal government we're talking about. Know what'll happen? The purchase cards will be pulled from every card holder who has *never* been dinged in an audit, but the clueless and/or criminal employees won't be touched.