The last window of opportunity for such an event would have been last weekend, because Corcoran State Prison only conducts inmate weddings on weekends, and the marriage license issued to Charles Manson and Elaine "Star" Burton expires this coming Thursday. (Los Angeles Times) But according to a spokesperson for the California Department of Corrections and (in General but Not in This Particular Case) Rehabilitation, "A Manson wedding did not take place." So unless they make a special exception for Charlie, and that seems unlikely, time's up.
I would object to the phrasing of the spokesperson's statement, which I think is not technically passive voice but still makes it sound like it's the wedding's fault, but "A Manson Wedding" made me think of "A Charlie Brown Christmas." And that was good.
I previously mentioned what appeared to be a gift registration for the purported couple ("The Mansons Are Registered at Bed Bath & Beyond" (Nov. 18, 2014)), and also posted this followup noting six more joke registries. If you did get them any gifts, I think they have to return them now, but I don't really know how that works.
Of course, the couple can always get another license and try again, but at this point it's starting to look like Chuckles will get paroled sooner than he gets married.