Flipsky 4.2 ESC go BOOM!?!

Hi,

I have a Flipsky 4.2 ESC. im using it to power my e-scooter motor as it is compact and reasonably easy to use. after weeks of tinkering around and getting PCB's made for other circuits on the scooter, I got to a point where I could finally test the scooter on the road to test its performance, I tested the ESC thoroughly using an Arduino to control it. for some annoying reason, just before I was about to carry the scooter out the front door, I turned the scooter on and tickled the throttle to check it was on, and guess bloody what... as soon as I gave it the smallest amount of throttle... I heard a pop from the area where the ESC was. after all that testing even under load, it died minutes before I went to test it on the road. 

inspecting the ESC revealed that there were no longer LED's showing on the board, even with a bench DC power supply. I removed the heatsink off of the back to find that the board looks pretty much perfect, I can't see any physical damage at all even under a microscope. As this board is at least £70 to buy... I would like to confirm from the pros that there is not something I can do to revive it, hence this post... 

Thanks in advance,

Arran.