This page by the Amazon Worker's Alliance describes the rights of workers when diagnosed with Covid-19 with the assumption of quarantine.
https://amazonworkeralliance.org/know-your-rights
After reading multiple articles about the case and the premise that he was fired, It is reasonable to think that the case between Christian Smalls and Amazon was reasonably judged, as he was responsible for other members of his job, took paid leave under the premise he was under covid, as well as getting caught, there is no reason to believe that the case should be revived.