Agreed....but placing a restaurant there could be done with the modifications as you stated....There wouldn't be room for a kitchen, so that would have to be at ground level with cart delivery to the platform (via the modified elevator system), and because there would be a view with limited seating, it could be by reservation only. The cuisine could be fine dining with a wine list, French cuisine perhaps. With a little imagination the park could have a real money generator.
If memory serves me, when The international restaurant was in full operation, wasn't it a Fancy shmancy sit down, reservation type atmosphere? That would tell me that it's been done before and it didn't work..