Whether the stuff about William is true or not, putting the protection of William and Andrew on an equal footing is a ridiculous supposition.
The royal family is all about the monarch and continuation of the direct line above all else. From birth William has been in line to the throne, whereas Andrew became further and further away from it after Charles had his sons. William needs to be protected for the continuation of the monarchy, although I doubt the palace has needed to do anything like the PR job on him as compared to what they obviously had done for years on Harry before he left the UK.
Andrew's dodgy relationship with Epstein and his misdemeanors and sleazy behaviour was exposed in 2011 when the photo was released, so he wasn't being much protected from that point onwards, whereas at that time Harry was still being portrayed as a cheeky chappie fun guy, so to say Harry had the heat put on him to cover for Andrew is wrong.