I don’t own a limenet micro. But if I did I would start at page 2 and 15 of the Schematic and cross reference the Bill of Materials. The damaged chip is probably acting like a short circuit instead of a regulator, which may hamper your attempts to in-circuit troubleshoot.
The datasheet for the LMZ10501 DC-DC stepdown regulator specifies an input voltage of 2.7 to 5.5 volts and an absolute maximum of 6.0 volts.
The datasheet for the AP7361 ultra-low dropout linear regulator gives a input voltage range of 2.2V - 6V and an absolute maximum of 6.5 volts.
If I was betting I would guess that you melted one of the four LMZ10501 chips, but if the voltage was high enough, any of them could have failed.