There's no way I can say this that isn't going to sound condescending, but it has to be said.
This story has suffered greatly on FR because of the number of people who post, as fact, things they don't know.
We would all be better off if speculation was labeled speculation, and "facts" were accompanied by links to where those facts were obtained.
In your post, you presumsed that most of the wives were in plural marriages when there is no evidence to indicate how many were in that circumstance, you presumed there was no birth certificates for most of the children when there is no evidence to support that claim, and your "not sure" statement is at least partly refuted by facts presented multiple times on FR about the records which were seized from the FLDS compound.
Well it's pretty hard to know who's "married" to whom and how many wives the various men had when the FLDS shredded most of the documentation.