No, I don’t see any reason to think this is anything other than a suicide - I accept that the man was severely troubled from all the evidence - but I am very annoyed at the police approach in this case.
Being suicidal or even mentally ill doesn’t stop somebody being a terrorist.
Apparently it does, "officially," if you're the right kind of terrorist. All those men shouting "Allah Akbar," for example, turn out to be "mentally ill," rather than Islamic terrorists.