The Bromeliad will make pups if it is happy, and crowd the Phal eventually. The Phal roots are thick and ropy, the Brom thin and wiry.
I haven't done this, I generally avoid mixing plants as it seems one always does better and they don't stay in balance. But who knows? Good luck and let us know, if no one answers specifically.
You may know this, but they say, do not let water puddle in the crown of the Phal, they way you do leave water in cups of the Brom.