Dear Carol,
I never heard of that sect and I don't think that those ideas represented by those people are Islamic in any sense. Qada'a and God's justice on earth has gone under many philosephical debates between many Islamic scholars and each has his own opinion. God would not force you to do evil neither do good it's up to you, and I exactly agree with you on why those people in Canaan were destroyed. That's the Islamic view of God's justice.
Thanks.
PS: ask more if you need clarifications.