It can say what it wants, but I've been affiliated with the LDS Church off and on for about 15 years.
Some members may feel a need to limit their association (outside of church) with those that leave, but there is no policy of shunning in the LDS religion. Even at that, they'd have to be really bad, but that's just common sense (removing toxic people from your life).
As a matter of fact, very few things can get you DF'd from the Mormon Church, one being Apostasy (but not much else), but there are no sanctions placed on you for associating with a DF'd member, even 'apostates'. It's actually the complete opposite, whereas they seek out those that have left the Church to encourage them to return. (not that that's much fun either)
A DF'd Mormon cannot hold a position in the congregation, and most likely is not considered to eligible for the 3rd level of Heaven, but still would be eligible to be 'saved'. They believe all of God's people are saved, regardless of religion.
Rev