No. One must first understand the definition of "positive law" to realize what is occurring in such a proclamation.
"Within the context of the US Code, positive law is used in a more limited way. According to the Office of Law Revision Counsel (US House of Representatives), a positive law title of the US Code is a title that has been enacted as a statute. To enact the title, a positive law codification (action or process of arranging laws or rules) bill is introduced in Congress. The bill repeals existing laws on a certain subject and restates those laws in a new form–a positive law title of the US Code. The titles of the US Code that have not been enacted through this process are called non-positive law titles. The laws assembled in the non-positive law titles have been enacted by Congress. Thus, in both positive law titles and non-positive law titles of the US Code, all of the law set forth is positive law (in the general sense of the term) because the entire US Code is a codification of statutes enacted by Congress, and not of natural law principles."
The reason Lawful Money is not enacted as "positive law" is because it has not been codified (re-arranged or changed). It is a remedy for the use of private credit, therefore the law needs no changing.
As a final note, because the U.S. Code contains only the “general and permanent laws of the United States,” (i.e. if it's in the U.S. Code, it's permanent / generally accepted), it
does not include “[t]emporary laws, such as appropriations acts, and special laws, such as one
naming a post office.” Off. of Law Revision Counsel, United States Code: Frequently Asked Questions and Glossary, http://uscode.house.gov/faq.xhtml (last visited December 15, 2020).
CONCLUSION: Positive law does not refer to anything that is "more sound or legal". It simply defines the nature of the laws history of revisions. If a code is in the U.S. Code, it is congressionally accepted.