I think that's why @RaceOncology states in the post I linked...

I think that's why @RaceOncology states in the post I linked that "Any drug that is approved is going to struggle to be tested in the clinic for a new indication. Pharma companies can’t prevent off-label use and if the drug is already generic so there is no incentive to pay for the trials needed to encourage doctors to use the drug for the new indication."

So unless I misunderstand it, it looks like the strategy is to get approval for the orphan indication and use off-label for other indications. No one is going to pay to run trials to get formal approval for any other indications because it would be self-defeating to spend all that money and then have no financial benefit as a result of the drug becoming generic at that point.