The council didn't choose a cheaper/unsafe cladding option, they chose a safe one (as far as they were aware), likewise the main contractor were under the impression everything was done to spec/code, the only real question as far as intent goes is if the (since liquidated) cladding company intentionally used the cheap flammable cladding to save money, or if they genuinely believed it was just as safe as the more fire resistant type (as implied by it's data sheet).If Kensington and Chelsea council had a meaningful conversation with the Grenfell Tower residents then they would have avoided the ambiguity of building regulations on cladding by using the safer cladding option.
One of the scariest things to come out of this sage for me personally is knowing I would have picked the same cladding with the data available, believing it met building regs.