Is there any code available I could run on a Teensy 2.0, so when I connect it to a Teensy-LC running this code, I can reproduce the lockup?
Actually, before that... have you tried 1.23-beta1 yet?
https://forum.pjrc.com/threads/28499-Teensyduino-1-23-Beta-1-Available
Quite a bit of work was done to the Wire library to prevent lockups with using the Lidar Lite, which does all sorts of wrong I2C stuff. Maybe 1.23-beta1 will solve the problems you're seeing? It's easy to try.
I do not have the Beta, I will try it. Should I switch to the i2c_t3 library?
Matt