Since I spend enough time with plenty of exmormons, I hear all sorts of funky things. I'm passing things along that I found on the internet, after hearing about these stories. Please note that I'm not claiming any of this is true (and that I just like speculating, which gives me a good probability that I could be wrong), but it is certainly interesting:
Julio E Davila: Davila was in the second quorum of seventies. That's pretty high up in the LDS church. Rumor is that he had an affair with a secretary and lives in Mexico city with her. Rumor also is that he doesn't believe in the LDS church. If that's true, he would be the highest mormon authority, that's known to not believe.
Terryl Givens: A devout Mormon professor in Virginia. He apparently knows all of the mormon history problems, yet says that he chooses to believe anyway. He's been going around Britain giving fireside talks about church history problems, and is going to do the same in Provo this July (2013). It seems that the church acknowledges 10 major problems with the church, and is going to roll out a 3-year plan of Church approved history books to deal with these (according to David Twede at Mormonthink).
The unknown seventy who doesn't believe:
Speculation is rampant among exmormon boards about which seventy met with Grant Palmer, which he gets a lot of flak for. I'm not sure why I linked to the FAIR blog... they have silly reasoning as usual, rationalizing that it has to be Carlos Amado, Claudio Costa, or John Dickson, and saying that that's impossible! FAIR's reasoning was that the GA had to have been a GA since 1995 in order to have intimate contact with the twelve apostles of the church.
Now, I'm certain that there's more than a few seventies who don't believe. But I present to you my theory. Now, since Grant has never actually told me any details regarding this seventy other than what was said on the Mormonthink blog... (*cough* ...actually, I thought it was Marlin K Jensen that Grant was meeting with ... I really don't think Marlin believes... *cough* I asked Grant, "What do you think of Marlin Jensen?" Based on Grant's response, that wasn't the GA he had been meeting with..) Anyways, since I don't have any more information than anyone else, I am free to speculate and post my speculation publicly. According to Grant, this particular GA doesn't plan on coming out, figuring the church will take care of itself.
Narrowing down the seventy:
Now, the people on Mormon Dialogue forums had two guesses: Lynn Robbins and Craig Zwick. The guess here is based on separating GA's by who is in Utah (or North America), who is in the first quorum (since Grant said specifically "First Quorum" and not "Presidency"), and since they have been in the seventy the longest, 16.2 and 18.2 years, respectively. Based on the familiarity with the apostles and the stages they go through, we can get rid of anyone who isn't in Utah, who has served under 10 years, leaving us with: Elders Walker, Golden, Snow, Robbins, and Zwick (in choronological order). We can remove Walker and Golden, considering they were in Asia and Africa most of the past decade, ensuring they would have less contact with the twelve. Snow can also be removed, since this June 2013 Ensign article by him is anti-internet and anti-learning. Leaving us with, Robbins, and Zwick.
Zwick is part of the correlation and missionary department. His construction company has also built many church buildings. He also is apparently a Republican (although Robbins donated the same amount), whose son helped out on the Romney campaigns. (Whoa! That's a huge TIE to the LDS church!) I don't think it's Zwick. Someone who didn't believe in the church couldn't be part of the correlation and missionary department. Someone who had huge financial ties to the church, where coming out as a non-believer, wouldn't have suggested that he would even come out, much less risk meeting with Grant because it could influence his construction company, his son's political job, and their financial future.
By the process of elimination, I present to you Lynn G. Robbins, who I suspect to be the apostate seventy who is meeting with Grant Palmer. Keep in mind, that this is all just a rumor (that I'm starting,) that has no basis in anything, other than the things that I've linked to on the internet.
Lynn G. Robbins: Lynn has a son who is openly gay. He currently has no role identified on the LDS church web site, giving him free time to just hang in Utah. His money is less tied to the church, although still tied with the Franklin Covey group. He talked about general Christian principles and hypocrisy in his last talk, where he ended with a generic testimony ending. He's been in the first quorum since 2000, second quorum since 1997, being in a position over the United States areas.. and considering the South American boom in the nineties where he was a mission president, would have had plenty of contact with those in the twelve who were stationed down there.
Whoever the apostate seventy is, it's a shame that he won't openly come out as non-believing. The world needs more heroes who speak up when they see something wrong; we're all in this together.