To answer your question regarding jumpseat qualifications. The FAA states that no one can occupy a cockpit jumpseat unless they hold a pilots license/FAA inspector license. Passenger and flight attendants are NEVER allowed to ride in the cockpit jumpseat.
On the topic of cabin jumpseats, only American Airlines flight attendants can ride a cabin jumpseat. At no time during flight may any other person sit in this jumpseat. One of the reasons that this is a qualification is because we have very specific emergency procedures. People that are not familiar with emergency evac procedures will get in our way and could cause us delay in getting doors open.
I hope this helps. Trust me when I say this, you don't want to sit on one of these seats. There not known for their comfort. Your butt hurts at the end of a flight
Wayne
Wayne