You know this article pissed me off with the self-immolation bit.
Self Immolation in protest couldn't be from preexisting mental illness. He clearly was emotionally impacted by his experience in the environment enough that his rational brain thought that by assuming such agonizing pain and stating the protest, the message would get heard a squeak louder.
Suicidal people don't think rationally. They want the pain to end. Or they become wildly careless. They don't sit there and go "how do I accomplish some good and end my suffering " while selecting the second worst way to die.