The government have bought armoured vehicles rejected twice by the Americans as unsuitable. Are they stupid?
I don’t think your theory is entirely correct. A more likely reason is that the vehicles mission will be different. The Americans kind of assume that their equipment is going to get blown up, so they are pickier. The Brits don’t ever expect to actually use them in combat, so durability is not as critical. Their purpose is to parade around and show support for the other countries who are doing the fighting on their behalf. Their purpose is more political than military. To that end, a token amount of bloodletting is desirable.