I think the fallen android with the red triangle with no command underneath is the stock recovery. The actual error should be in the recovery menu accessed by holding down power, pressing volume up and releasing power. You can factory reset from this menu which seems to be what the op has done. Using a toolkit is an excellent idea, I would flash the factory image as well since it's already been reset. That would reload all the system apps in case they were altered by a root enabled program.
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