The routing number on a Treasury check is to a bank in the Treasury Department. The routing number for a 'regular check' is like an IP address, the first two digits showing which Federal Reserve district the 'bank port' is hanging off of and ..well you know where that leads: as in the first two digits are prima facie evidence of the issuer being in a Federal Reserve district.
Routing number is a convention for the postal/courier side of banking system. Thusly it is always an FRS issue if the routing number associates with a Federal Reserve district per ABA convention. If it points outside the FRB then it would likely be Treasury matter especially if its not a domestic item.
Likely you can prod the FBI or the Treasury or the US Attorney to find something illegal about unjust weights and balances, racketeering or conspiracy against rights. If you have registered your 'plate' or 'stamp' with the Secretary I would say they would have to be bold to be willing to lose teeth in quantity. Remember, you mentioned "subordinate government". If you are assisting the treasury in carrying out their duties out of necessity, they would be interfering with official duties or with the exercise of ministerial powers. You'd, privately, be a treasury agent for all practical purposes. BTW, where do they get their licenses from? One can add that "I'm assisting you..." + a claim of your rights to do the redemption to the memo.
I have been in the position where I had to exercise duties because someone else would not. Being bonded against errors, omissions or the like would likely help immensely.