That’s basically what I’m thinking, but he needs to find where that happened because it shouldn’t. If it cut through a wire insulator somewhere so it could make a short, he needs to find it.
I reread my original comment and I should have said short to ground, but for the purposes of this...
it sounds like you had a short to power. check the battery leads very carefully. check the connector to the ESC. it shouldn't be on the esc to motor wires as you were not on the throttle when it happened. unless the hit knocked something loose inside the ESC allowing an internal short...