These guys will breed there is no denying that, just wait and see, you will wake up one morning and find yourself having a fresh new batch of fish, just remember to give them plenty of cover.The females can still give birth several times without the male.
Just some friendly advice, you may want to get more females because the males will tend to harrass them constantly if there are only 2. If you have more the males won't usually just be pesting 1 or 2 constantly.
What are your water parameters? I've never seen mollies NOT breed because of some pH or something, but if something is way off it may prevent it from happening.
Again, if the male is constantly pestering the females you may not end up with any fry because they will be too stressed to produce any. It happens sometimes.