Flipsky FSESC 4.12 won't power on

I have 2 Flipsky FSESCs like the one seen in this picture . A couple of days ago, one of them got disconnected during a ride and after re-connecting it to power, it won’t power on. No LED lights, nothing. I probed the 5V rail and I’m getting 5.1V, but when I probe the 3.3V rails, I’m getting 0V. The fact that I’m seeing 5V leads me to believe that the DRV8302 chip is working as it should be by stepping down my 6S pack(25.2V) voltage to 5V. The VREG (579-TC2117-3.3VDBTR) on the back of the FSESC, however, is heating up and I’m pretty sure it’s dead.

I assume that once I replace the VREG, it should power right up and things will work as expected. But, in the case that it doesn’t, I’m wondering if I should be keeping an eye out for any other components that could be causing the issue. Any help or insight is greatly appreciated.

Bonus question: Does anyone know why the act of an ESC disconnecting mid ride would have caused that?

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Update: I learned that if a VESC based ESC is disconnected from the battery during a ride, and you attempt to brake, regenerative braking will kill the ESC because the power has nowhere to go.

I began buzzing out the FSESC with a multimeter and realized there’s a short between the 3.3V rail and GND on the entire FSESC. I desoldered the VREG and the short remains. I’m waiting on a hot air reflow station to arrive in order to desolder the MCU. Once the MCU is removed, I’ll check on the short and report.

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