Ever since H&M decided to leave the RF (and specifically the manner in which they choose to do that) I've felt they are both highly naive in their understanding of how much public interest stems not from them as couple, but from their ties to the monarchy.
Their interviews/book garnered attention because it provided insight into the private life of the RF.
As the rift continues, the reality for H&M is that so does their access to new content/revelations and I think H&M have a very overstated sense of their own importance/platform as an independent couple when their profile is dependent on milking an historical association with an institution they clearly distain and family they hold in contempt.
The reaction to these names being made public is quite telling in comparison to the outrage post Oprah and has for the most part reflected worse on H&M than the RF.
Put bluntly, if you are going to make serious allegations stick then you are going to need credibility when making them.
Unfortunately for H&M their credibility is shot through their own repeated output of mis-information, outright lies (to the extent of being publicly chastised in court) and contradictory messaging.
It's also worth pointing out again that M has been out of the RF longer than she was in it and I'm not seeing anything from her or H in that time that's cemented anything worthy of being a global power couple in their own right.
Continuing to make money from the past only serves to highlight the fact they have nothing else to offer.
Ultimately the RF don't need to "do" anything re: H&M other than keep their distance and grey rock.