Why Wasn't Rainmaker + Burnout part of this movie?

Because it was really a pilot not a movie. They would of introduced them later in the series if it got picked up.

I don't remember Burnout having a cameo but I think Fairchild was in a sparring match with Rainmaker

I know it was based a lot on the original mini series

In addition to the sparring scene she shows up near the end when Ivana floods the dorm with knock out gas. She tries to use the intercom when find her door lock saying "This is Sarah Rainmaker something is wrong wiith door" then passes out