Match-up advice pls!

I'm not the best player, I am well aware, but I was really stumped on how we should have played this match. There were arguments among my teammates about who to aim first. Obviously the most apparent answer would be NOT Cho'gall, but our Hammer insisted on focusing Morales, and dove in to her death numerous times.

While my team was preoccupied trying to stop backdoors from Chogall Valla and Morales, the Vikings were just soaking lanes, and under 10 mins in we were 3 levels behind.

What would have been the ideal play in this situation? Was there anything we could have done, or were we just screwed from the beginning?

Match-up:

Allies: Zagara (myself), Kharazim, Anub'arak, Sgt. Hammer, Li-Ming

Enemies: The Lost Vikings, Valla, Lt. Morales, Cho'Gall