I would have to agree that it is NOT lightning,,, Lightning would rip a strip of bark down from the Crown and almost always a spiraled effect,,,, removing large chunks of wood with it... and sometimes blowing a hole in the ground,,,
as stated some live through it,,,,, some are dead within a week,,,,,
Also you have been given good advice to expose the root flair,, and aireate the soil out as discribed by sunrise and treeseer,,,, exterminate pest get your mulch build your berm/swale, make it look like a volcano sloping down toward the tree taking care not to re-cover the root/buttress flares,,,,