Sin Cara noted the following on his Twitter account:
"Back in Mexico from my knee medical checkup, everything is good, soon I'll be back in the ring."
Sin Cara will not be at the SmackDown taping in Richmond, VA. He is still listed on the WWE live events page, though. It's possible he's taking longer to recover than originally expected and he was advertised by mistake as a result. We'll keep you posted as we hear more.