The point is very basic: These "models" don't tell you anything about the human language faculty. They can be useful tools but don't serve science.
Chomky's point is that there is a lot of evidence that humans don't use a statistical process to produce language and these statistical "models" don't tell you anything about the human language faculty.
Whether your 1 & 2 are meaningful depend on how you define "model" which is the real issue at hand: Do you want to understand something (science) --- in which case the model should explain something --- or do you want a useful tool (engineering) --- in which case it can essentially be a black box.
I don't know why you care to argue about this though; my impression is that you don't really care about how human's do language so why does it matter to you?
