It might seem obvious but does it open if you use the key in the boot lock. If yours does not have a boot lock (some models did not) drop the back of the rear seat down to give access to the boot and take off the boot lid inner panal which will give you access to the boot lock and then you will be able to open the lock from inside. All you have to do then is find out why the boot lock was not opening with the central locking (Multi meter to hand)
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