Does the male Horsea/Bagon have the move you want to pass down in its current moveset? If not, there's your problem.
i have a male horsea and it has agility, and when i put it with a female piplup the old guy said they don't like each other.
i have a male dratini who has dragondance and a female bagon, and the old guy said they don't like each other too.
do they still give you and egg even if the guy says they dont' like eachother?