In one study they fed both monkeys a highly processed diet of 30% sucrose. In the other study they fed both monkeys a less processed diet of 4% sucrose.

The monkey with the poor health outcome was the one allowed to eat as much as it wanted of the highly processed 30% sucrose diet.

So the "calorie restriction" seems to more likely just mean "don't eat more than 4% sugar, unless you are on an extremely calorie restricted diet."