I've set the Brand to hide the Help and About links but they are still showing for some reason. This is the only Brand I have configured so it is definitely using this one.
As a test I set my own Help Text and URL, which I was immediately able to see, so I cannot figure out why the hiding option isn't actually working.
Turns out this feature only works if you have it enabled for your account.
By that I mean, that if you just create a brand and check the boxes to hide these links - the links will still show.
You will need to contact either customer support or your account representative to enable this functionality in your account.