The GTI said sod the Shivans and kill the Vasudans.
No, they didn't. You're mixing G-canon with real canon.
(G-canon = Goober/Galemp canon 
)
They didn't in G-canon either.
They said kill the Vasudans, but not until
after they've helped us kill the Shivans. They were smart enough to realize they couldn't fight the Vasudans and Shivans at the same time.
I makes me wonder if the Trigger Happy Terran pilots who caused the skirmish at the beginning of Vanilla ST were trigger Happy Co-conspirators...
That would have been a nice plot-point to include in ST:R...but oh-well.
At one point it
was, but we decided it was too confusing and didn't really add much to the story, so we took it out.
