Although I understand that the ex-wife's statement fits nicely into the desired belief that the parents are responsible for the actions of their 15 year old son, what I hear in the statement is an ex-wife who is angry about the amount of child support she was allowed to receive, angry that child support was unpaid, and not happy about her ex-husband's wife.
I don't think anything she said has anything to do with the shootings. Realistically, a man who had three children with three different women did not raise three children to shoot children at school. One of the three children clearly has psychological problems that were not addressed by the school, the police, or the parents.
The drawing was clearly a cry for help, very likely help for something that was happening in the school. The school's decision to have him removed from the school, rather than address what happened in the school to trigger the psychological problems, was perhaps the straw that broke the camel's back.
If the child shooter was bullied at school and no one did anything to help, how is telling the upset child to leave the school helping? That's blaming the victim.
"Investigators said they are still trying to determine a motive for the deadly shooting because the suspect isn’t speaking to them. However, some
classmates have said Crumbley was bullied,
according to the Detroit Free Press."
Michigan school shooting suspect identified as Ethan Crumbley