1 1/2 year male old Golden and a 9 month old female Chocolate Lab?

I have a 1 1/2 yr male Golden Retriever and I have an opportunity to rescue a 9 mo. female Chocolate Lab pup. My Golden would LOVE a friend to play with but the pup has been an outside dog and is not housebroken. Will she teach him bad things while learning to go potty outside? I plan on getting both fixed right away. Is there a way to tell who will be the alpha? It is automatically the male? Geez that sounds really ist!! I have never had a male and a female just 2 females and it was disastrous!!