Roguaran

I caught a Ditto from the rift den on route 4, but get the fatal daycare message when trying to breed it with anything of "the two prefer to play with other pokemon." I really need to breed this Poliwhirl since I need a Poliwag for the Neo-Gearen quest line but it's a male Poliwhirl so I need it to breed with Ditto since I don't believe anywhere has wild Poliwag until after the help quest has been completed. Any advice or help would be greatly appreciated!