Because he gave a lot of money to the Scottish Rite.
Kinda like why Ted Kennedy is to be buried in Arlington National Cemetary and was able to buy an annulment from the Roman Catholic Church.
He was an “important” guy.
Doesn’t mean he wasn’t a loser.
Actually, there has been no confirmation of an annulment of Ted Kennedy’s marriage. You may be confusing it with the “annulment” of his nephew Joseph’s marriage granted by the Archdiocese of Boston, which the Vatican overturned in 2007.