go to b&q get a length of 15mm copper pipe.
hammer it flat.
cut a V shaped notch near the end.
carefully pull the top rearmost corner of the driver's door out, use some wedgey shaped bits of wood to help hold it out.
just enough to get the pipe in and hook the boot release.
You may need to bend your flattened bit of pipe this way and that to get it too the right place but it's do-able.
You may have to manipulate your door back into shape afterwards!
And no, I'm not a tea-leaf.... just locked my keys in my car too many times - just happens the first time I was doing some plumbing and had a hammer to hand. It's worked on 3 cars so far.