Andrew Lownie's suggestion that they both voluntarily relinquish their titles and go and live somewhere out of the public eye is, for me, the best compromise and most sensible.
I think the British public are sick to death of all the ridicule and embarrassment that their parents have brought upon the country and I can't imagine anyone being sorry if we never hear of them again. Whilst I think there's an element of blame by association with regard to their daughters, I'm afraid I don't believe they're squeaky clean. They may not be at the centre of the tangled web woven by their parents, but they're certainly on the outer perimeter.
Frequent, extravagant holidays, gifts of expensive jewellery and goodness know what else seems to have been their normal lifestyle.
They both have wealthy husbands, I'm sure an address book that's like the Yellow Pages of the wealthy, so wherever they are, they won't be going hungry.