They were very careful because passing it off as if it were government money would be a crime. Despite not doing this, they have been lied about to the point that even you are misremembering.
There are many reasons to decide to not be involved with the liberty dollar-- not the least of which is the indoctrination that "money" must come from the government, something I had to overcome myself. But the claim that they were pretending it was government money is not one of them.
The entire point of NORFED-- the National Organization for the Repeal of the FEDeral reserve-- was that government money was not as good as silver rounds.