Have the Decidueye with the Hidden Ability (HA) breed with a Ditto, there is a 60% chance that it will pass down its HA. Do this until you get a female Rowlet with the HA, since females have a 80% chance of passing down their Abilities. Then pair that female with the male that has perfect IVs, give that male a Destiny Knot so that it will pass down 5 off its IVs to the offspring.
Feel free to switch the original female with one from the eggs you hatch if you think it would work better, if the mother has some IVs opposite to the male then eventually you'll get all the stats you want since IVs are inherited from both parents.
Good luck!