Iger did not bring in Lassetter. He came with Pixar and Steve Jobs insisted that he be made Chief Creative Officer and run the combined animation studios as well as WDI - or it was no deal.
This absolutely 100% completely not true. Disney animation was on its deathbed. The studios most recent animated movies were complete flops (Atlantis, Home On The Range, Brother Bear, The Wild, Chicken Little) and Iger realized that Lasseter was the man who could revive Disney Animation.
Getting Lasseter in the deal to head Disney Animation was an enormous bonus, not something Iger was forced to do. If anything, Iger wouldn't have accepted the deal if Lasseter weren't part of it.
And, by the way, as I understand it, Lasseter is not the head of WDI. He's Chief Creative Officer.