any chance it was murder? Presence of drugs? Someone bought the acceleraant?
What I recall I read in one article was that she sent videos out to her ex and maybe someone else and it was unusual enough the ex-husband called her mother to check on her, that next day. Her mother went to the home and saw her daughter in flames or all burnt up and begged for water and said she didn’t want to die. The mother called 911, but the daughter died later died.