That's a great point about the bond. For the peanut gallery, in a civil case, when a party is temporarily (as opposed to permanently at the conclusion of a case) enjoined, so by TRO or preliminary injunction, the party seeking the injunction has to post a bond against damages the enjoined party may suffer if the injunction proves wrongful. So, sometimes it's a pretty substantial bond.
In public-interest cases with the government as a defendant, the bond is often waived. But by the wording of the statute, the bond could be set at $1, or $20, and the whole issue is avoided.
I assume "appropriated funds" gives Congress the hook to legislate, probably invalidly. Although I'm sure they'd argue they have the power to determine jurisdiction and this is a jurisdiction issue. And I think just about anything a US District court, funded by appropriated funds, does then would be in violation of the statute.