Let's say both pilots passed out , is there anyone else from cabin crew that is trained enough to land a plane?
To put it short: no.
Unfortunately it might even take a while for anyone to notice both pilots are out. Most likely the first would be an air traffic controller since he/she couldn't reach the pilots on radio.
If the cabin attendants find both pilots incapacitated, they would most likely
try to find a doctor or nurse to help recover a pilot
try to find if any of the passengers was a pilot