Thanks for all your suggestions, will consider and use a few. I am also thinking I need something with me that I can use when I am out and about.
I am still waiting to find out from Lexus dealership how they got it, but on the CCTV it took 50 seconds, they were doing something on the front passenger side before the driver jumped in and took off with the other guy walking off in same direction. I suspect it was CANBUS.
The 3 wires stripped in the boot afterwards was I guess to stop the alarm going off. When I got it back the car would not lock plus reverse camera not working. I took video of the car immediately I got to it and I cannot see any damage to the front passenger side. They had changed the number plates so looks like it was a professional crew.
I am thankful that the tracker worked and I got it back. Just don't want to lose it again!