If you are afraid that the garlic flavour will be overbearing, reduce the number of garlic cloves.
As garlic loses a lot of its healthy qualities when heated, this should ideally be avoided when preparing ice cream (no problems with this recipe). For similar reasons, the yogurt should not be heated either, and only added at the "chill-stage".
Another way to get a milder garlic taste is to to let the peeled, un-crushed cloves (possibly minced, but that will again increase the flavour) either infuse in (a) the milk/cream, or (b) in the honey (if the honey-method is used, preferably overnight, or even longer). After the infusion has been done, you could then discard the cloves/minced cloves. This will make the garlic flavour less intense, which might prove useful for some.