There is nothing secret about RNA testing. Any decent lab can synthetise its own markers from a file downloaded from internet. It is like genetic research is illegal in US or what.
Offering a diagnostic test without FDA approval is illegal
Only if they charge for it.2) The reagents needed for the testing are also in extremely short supply, and labs are having a hard time getting more. So, you can develop a test, but your testing capacity will remain limited.
*unscientific guess for literary effect