you can pick the lock if you know where it is under the seat. I don't have a 300 so I have no idea, but it's just a little hooked arm that you can compress if you have a long thin screwdriver or pick that you can fit underneath the seat. and a thin pen flashlight. it'll take some fiddling but it definitely can be done. I'm going to guess it's at the center of the seat either towards the back or towards the front of the passenger seat.. if it happens again