"If the battery is disconnected or discharged the gear selector lever will remain in park position."
This is a quote from the 2008 manual. I have not read the 2009 manual - is this the manual you are referring to?
I doubt that the 2009 is any different for flat towing than the 2008. I've been towing my 2008 car without need to disconnect the battery. What could be the possible reason for disconnecting the battery?
To tow, the key is inserted in the ignition lock and turned to position 1 without starting the engine, gearshift moved to neutral position, then key turned back as far as it will go which turns off power. The key cannot be removed from the ignition lock with the gearshift in neutral but that is not an issue. Carry an extra key just in case the door becomes locked.