Just have to play it right. Slip in some details, get curious about what food you can order to your room, etc. You can always decide some detail is a deal breaker & not make the close
Or just be explicit and share. "Hi, I need to extend my stay from 3 nights to 2 weeks. I'm just returning from a high risk area of Italy and need to quarantine myself!"
"and I want to do it somewhere with a gym and pool"