When you manually unlock the car, you need to put key in ignition and turn on w/in ~ 20 seconds or it sets off alarm and immobilizer. I presume she did not which leads to at your your one other problem... alarm horn not working.
Have you tried to start car yet? This should resolve. If not, try locking car manually with doors closed from outside. Wait 1 minute (for alarm to fully arm). Then unlock it w/ key and within 20 seconds, insert key into ignition and turn to on position (or start it). This should reset for you and re-enable key-fobs (or you may have an issue w/ either the fobs or alarm control unit under driver's seat - fresh batteries in key fobs will help too). Otherwise, you'll need to find a shop w/ the PSTII or PIWIS Porsche diagnostics system to find fault codes in alarm system.
Your alarm horn is NOT the same as your regular horns on the car (behind the front bumper). Instead, it's located up by the battery in frunk. There are some other nuances and a manual wire release for the frunk so please help us help you by stating your model year in posts.
Good luck
