There isn't any new news on Andrew for there to be a gagging order on. He was asked to go voluntarily to the US to tell investigators what he knew about a case which a friend/acquaintance was involved in. He declined. Girls in a state of the US, above the age of consent in the UK, but just below it in that state, have said that they were procured for his delectation by the said acquaintance/friend, but no charges have been brought.
His mother wasn't pleased with him for his links with the sordid affair and took what action was open to her to show this - she sacked him from the family firm and stripped him of his positions and perks. As he is well over 21 she has no more power over him than any other mother over a full-grown son. If the US legal system wishes to force him to attend a police station in the States, it is up to them to make it happen.
Everyone is free to think what they like of his attitude, morals, and common sense, and the media are free to publish anything of which they have proof. If they have no proof, they run the risk of being sued for libel. No need for a gag.