I don’t think Smith-Mundt fits either. The mode of perpetrating this hoax was not via preparation of propaganda. It was official actions and leaks to the press, based on a known lie. No government funds were expended, beyond the usual overhead.
If I'm not mistaken I believe ohr and a few others got bonuses that year and/or raises. That is expenditures which would have to show it tied to their actions. That could be done by showing their job performance wasn't unusual to warrant such a bonus with the exception of these lies.