The huge problem in hindsight was that parishes proposing to come in from Anglican denominations -- which was the point of the whole thing -- needed a great deal more preparation than they received. Whoever was the shadowy figure in charge of the transition during 2011 appears to have approved the catechesis St Mary's received, which on balance was good, but many things were left unsaid. It was the case at St Mary's, but also clearly at other parishes like St Aidan's Des Moines, that there were good Anglican members who were in what the Catholic Church would call irregular marriage situations.
Nothing was said about this in any detail during the catechism -- it wasn't in the class materials, as far as I can remember -- and, other than an e-mail that went out to the parish in December 2011, nothing else was said. The e-mail basically said very briefly that if you're divorced from a living spouse and remarried, you'd better start working with the Archdiocese of Los Angeles. (Wait a moment, shouldn't the Ordinariate be the authority here?)
However, every source I've seen suggests that the process of getting a declaration of nullity from a diocesan tribunal takes at least two years. Since serious announcement of the US-Canadian Ordinariate took place only during 2011, it should have been clear to someone that some members in any former Anglican parish, however sincere they may have been in their intent, were going to be in a situation where they could not be received as Catholics with the rest of the parish. Yet no plans were made for how to deal with this situation.
This appears to have been a major factor behind the decision of St Aidan's Des Moines not to enter the Ordinariate after all in spring 2012. Msgr Steenson traveled to that parish in some effort to clarify the situation, but oddly, even though he must have been aware since 2007 that something like this could be a factor, the most he could do was tell that parish that yeah, that was how things are. They'd already hired a priest who'd take them into the Ordinariate, but they backed out.
I don't think you can blame the Anglican priests who were involved with the process. They'd been working as Anglicans and had been providing pastoral care to Anglicans whose marriages were regarded as OK in that denomination. As far as I can tell, there are Catholic parish priests who do have experience with handling situations where Catholics may (for instance) be returning to the Church after some time away, during which a divorce and remarriage may have occurred. There appear to be viable if difficult pastoral strategies for handling such situations, awkward as they may be, and couples do in fact deal with them.
But, notwithstanding how likely such situations might arise, nothing was done to handle them (or even, apparently, mention them) in the runup to the US-Canadian Ordinariate -- except that Msgr Stetson, the St Mary's chaplain, took a very Anglican approach, if not a Catholic one, in saying he didn't "check passports at the communion rail".
The inception of the US-Canadian Ordinariate was a fiasco, which can be laid at the feet of completely inadequate planning by the authorities in charge. There are other areas where action might have been taken but wasn't.