My advice is to immediately rebrand as gracefully and effectively as possible and use all that activist energy to effect the transition.
They kind of have a point which doesn’t make them right, but they hold all the cards and you will lose this one and regret the wasted bandwidth.
They don't (the claim is the app promotes drug use, which it doesn't), and it's quite likely that it's a reviewer mistake that will be overturned once the stink on social media gets big enough to reach the right person.
You don't think it could reinforce the idea that Amphetamines could be a useful tool to preserve wakefulness?
I don't think we as a society should be this sensitive/prone to suggestion. If anything, I believe the censorship promotes the idea that people have no responsibility to make their own choices, and we must build to the lowest common denominator.
Note, I'm not really making a judgement about whether Apple should be allowed to do this - I think that is harder question.