Probably the best set of recommendations is that of George Weigel from last Monday (click on this post's title). The blogspot In the Light of the Law, which is by a canon lawyer, had some similar ideas the last time I checked, a few days ago. Someone outside the Legion could head an investigation and come up with a plan to straighten out the whole situation.
Any sincere Catholic has to admit that there are many wonderful Catholic priests in the Legion, and many good lay Catholics in Regnum Christi. Many or most are reacting in the right way: Feeling betrayed, being angry at Fr. Maciel's years of deception and double life, feeling sorry for the victims and wanting everything to be exposed, cleaned up and made right.
A big part of the deep hurt in the wake of the scandal, as I understand it, is that the Legionaries and their lay allies essentially were never supposed to question or doubt their founder and his wishes. They are now upset, to put it mildly, at that policy and at Fr. Maciel's defenders.
No one, even liberal Catholics, should want to see all the good that the Legionary priests and Regnum Christi members do be shattered. Maybe the Legionaries eventually will be reconstituted, and Regnum Christi too, and the good their members do can continue in that way.
Does the scandal mean that those who have disliked the Legion and Regnum Christi for their orthodox Catholicism were right? Not if what they disliked was just the orthodoxy, of course.
If you know any Legionary priests and any Regnum Christi members, reach out to them, let them talk out their feelings if they want to, and be kind and encouraging to them.
Let us hope and pray for the best.