Question: In what year did the bank robber who inspired the movie "Marilyn" die?

Context articles: Attila Ambrus
Willie Sutton
Willard Erastus Christianson
Johann Kastenberger
The Dog (2013 film)
Paddy Mitchell
Marilyn (2011 film)
The Bank Dick
Salvatore Naturale
Butch Cassidy

Attila Ambrus (born October 6, 1967), alias The Whiskey Robber is a Hungarian bank robber and professional ice hockey player.
 He became notorious during the 1990s for committing a string of undercover "gentleman robberies" in and around Budapest, Hungary, while working a day job as a goaltender.
 He became infamous in Hungary as a folk hero symbolic of the times in the decade after the introduction of capitalism to the former Communist state.
 Ambrus was eventually caught and imprisoned for about 12 years, released in 2012.
 His story was made into a book, "Ballad of the Whiskey Robber" (2004), by author Julian Rubinstein, which has been optioned by Johnny Depp for a possible film adaptation.
William Francis "Willie" Sutton, Jr. (June 30, 1901 – November 2, 1980) was an American bank robber.
 During his forty-year robber career he stole an estimated $2 million, and he eventually spent more than half of his adult life in prison and escaped three times.
 For his talent at executing robberies in disguises, he gained two nicknames, "Willie the Actor" and "Slick Willie".
 Sutton is also known as the namesake of Sutton's law, although he denied originating it.
Willard Erastus Christianson, also known as Matt Warner, Ras Lewis, and The Mormon Kid, (1864 – December 21, 1938), was a notable figure from the American old west that was a farmer, cowboy, rancher, ferryman, rustler, bank robber, justice of the peace, lawman, and a bootlegger.
 He operated in the Robber's Roost area of Utah before teaming up with Butch Cassidy.
 While on the run from the law he married Rose Morgan.
 For a while he operated a cattle ranch in Washington's Big Bend Country.
 Later he operated a ranch on Diamond Mountain in Utah.
Johann Kastenberger (born October 1, 1958, in Sankt Leonhard am Forst, died November 15, 1988, in Sankt Pölten, Lower Austria) was an Austrian marathon runner, bank robber and murderer.
 He infamously committed his crimes while wearing a Ronald Reagan mask, earning him the nickname "Shotgun Ronnie".
 Kastenberger's criminal life was the basis for the 2010 film "The Robber".
The Dog (also known as "Storyville: The Great Sex Addict Heist") is a 2013 documentary film co-written and co-directed by Allison Berg and Frank Keraudren, about the real life story of bisexual bank robber John Wojtowicz that inspired the 1975 Al Pacino movie Dog Day Afternoon about his August 1972 attempted heist and 14-hour televised hostage situation in Brooklyn to pay for his lover's sex-reassignment surgery.
Patrick Michael "Paddy" Mitchell (26 June 1942 - 14 January 2007) of Ottawa, Ontario, Canada, was leader of the notorious "Stopwatch Gang" of bank robbers.
 Mitchell was on the Federal Bureau of Investigation's most wanted list for the Stopwatch Gang's bank robberies across the U.S.
Marilyn is a 2011 romantic crime drama film written and directed by Christopher Petry, starring Ryan Robbins and Allison Mack.
 It is based upon the true story of Paddy Mitchell, a notorious bank robber who was part of the Stopwatch Gang, who appeared on many of the top FBI most wanted lists during his tenure as a criminal.
 The film is noted for having been released via Distrify, a video on demand system which allows for the distributor to make money from the film via either rental or purchase.
The Bank Dick (released as The Bank Detective in the United Kingdom) is a 1940 comedy film.
 Set in Lompoc, California, W. C. Fields plays a character named Egbert Sousé who trips a bank robber and ends up a bank security guard as a result.
 The character is a drunk who must repeatedly remind people in exasperation that his name is pronounced ""Sousé – accent grave" ["sic"] "over the 'e'!""
, because people keep calling him "Souse" (slang for drunkard).
 In addition to bank and family scenes, it features Fields pretending to be a film director and ends in a chaotic car chase.
 "The Bank Dick" is considered a classic of his work, incorporating his usual persona as a drunken henpecked husband with a shrewish wife, disapproving mother-in-law, and savage children.
Salvatore Antonio "Sal" Naturale, also known as Donald Matterson (c. 1953/1954– August 23, 1972) was an American bank robber whose attempted robbery of a Chase Manhattan bank branch in Brooklyn, along with John Wojtowicz, in August 1972, inspired the 1975 film "Dog Day Afternoon."
 In the film he is portrayed by actor John Cazale.
Robert Leroy Parker (April 13, 1866 – November 7, 1908), better known as Butch Cassidy, was a notorious American train robber and bank robber, and the leader of a gang of criminal outlaws known as the "Wild Bunch" in the American Old West.