I doubt Iger's opinion is what caused the delay. This delay is costing Disney money, not to mention the embarrassment of releasing a date and then having to cancel last minute. Even if the CEO hated it, you put the show out there and work to integrate changes in the weeks after.
That said, RoL does seem to be the sort of thing Iger wouldn't like. Original concept and music, no Disney characters or IP, symbolism and abstract show elements, a storyline geared toward appreciating nature rather than retelling Disney movies... There's not much chance for "synergy" with this one, which means it goes against everything that he thinks the parks should be.