The LDS Church does not give approval for any temples to be built on other planets, therefore there is a large temple build near ESM to take care of the temple needs of LDS people living off world. This is alot of people, when you consider that a large part of the Planet Mexico population is LDS. the LDS population in this area has therefor increased greatly, so Jason would have been surrounded by LDS people here, also, which would have been comforting to him after his stay on HomeWorld .
In Desmond's time Linked Paragangians cannot be members of the church as Memory Implants are strictly not allowed. Desmond is excommunicated when he becomes Paragan . After Harris gets permission for Linked Paragangians to be baptized, the ESM temple is adapted to block connection to the Community Mind , Such that a Paragangian cannot use his link while in the temple.
edit: as of Nov 2012, In History of Paragangia, Desmond's excommunication is not for having an implant, but for publically denouncing church leaders because Paragangians are not able to join the church. When he became Paragangian he did not get excommunicated, he just lost all his standing other than membership. I am going to check the doctrines on this and make sure it corresponds well with how such things have been historically handled, such as the early church not giving preisthood to people of african descent, etc.
History of Paragangia turned out to have very much LDS content because GLoria invites the missionaries over so she can learn more about Desmond's beleifs regarding marriage, and in the process of educating her they inadvertantly convert her father Jamie Scott. IN writing the novel I did not intend for this to happen, but given his personality faced with this situation there seemed no other option. In the spirit of NaNoWriMo, I went with it.
Because of this, Gloria and Desmond Go to church on HomeWorld several times in the story and they attend Jamie's baptism in Florida. GLoria attends two missionary discussions and then discusses them with Jonathan and Desmond. They also attend Jamie's LDS funeral.