Use this link, page 3 to get the details of where and how to drill behind the license plate to get access
I Can't Open my Boot

Then use this link to install a hidden emergency release strap.
Emergency Boot Access

 

I tried both of the suggestions for jump-starting the car from the fuse box and front wheel well. Neither worked for me, I suspect because I had removed the negative battery terminal before doing under the hood.

What did work was connecting jumper cables to the positive and negative terminals on the starter. Located under the passenger side near where the engine and transmission meet. The cables on the starter are red (+) and black (-). This did require jacking up the vehicle to access the underside. Make sure to secure the vehicle well before getting underneath it.

​​​​​​Once the jumper cables were hooked up to the starter I was able to start the engine from inside the car and then pop the trunk. It may or may not have been necessary to start the vehicle. I suspect that having the alternator running helped.

The trunk also seemed stuck, so one person pushed the trunk release button while I pulled the trunk open.