I wouldn't challenge it either, if I were in their situation. Being in quarantine would prevent me from infecting my friends and family with the virus if I happen to have it and CDC has shown evidence that it may be transmissible while asymptomatic. Furthermore, if I happen to be patient zero in a transmission chain that happens to start a pandemic in the US, I will be persona non grata with my face plastered all over social media, ESPECIALLY if it turns out that I challenged the quarantine that could have prevented it.