All of those carry the same risk. Hijackers can make a flight attendant tell air traffic controllers anything. What would work is an always-on video feed from the cockpit to galley — and a policy that any adult passenger is allowed to take at least a brief look at it upon request to a flight attendant, except when required to be seated with belt fastened due to take-off, landing, or pilot request over the PA system (i.e. due to turbulence). We need to take away the security pilots have (greatly enhanced now, with the locked cockpit requirement) that nobody can see what they’re doing.
BTW, they became aware of their plane's position only after a flight attendant asked about the landing time over the planes intercom, according to the NTSB. Otherwise they might never have checked their position until they ran out of fuel.......