The main danger of setting the phase current setpoint to a high value is that it may exceed the dynamic range of the phase current measurement front-end. This condition will cause the current controller to overload either the inverter or the motor, or both. The normal operating region of the phase current measurement circuit for Myxa is \pm{}50A; brief excursions up to |53| A are acceptable, although the front end exhibits non-linear gain in this mode. The maximum setpoint shall not exceed |45| A. Here is a relevant excerpt from the datasheet:
Setting the maximum current to 80 A is risky because it allows the controller to ramp up the phase current up to that value after stage 5. Synchronization of the spinup sequence is finished, which will likely cause saturation and overload:
If the failure is caused by saturation, then the most likely victim is one of the power stage transistors. The part number of the transistors is Infineon BSC040N08NS5ATMA1.
If the failure is caused by a voltage spike, then the most likely victim is the step-down DC-DC converter; however, it does not seem to be the case here as the board remains otherwise operational, so the DC-DC converter must be functional.
You can try and investigate this by running the self-test command:
This topic may also be relevant: ESC Myxa and Komar DC Power Wire Lengths Added Capacitance