Question: Are both John Tardy and Jun. K vocalists ?

full_context: Document 1: Troy Sanders: Troy Jayson Sanders (born September 8, 1973) is an American musician, singer, and songwriter best known as a member of the Atlanta, Georgia metal band Mastodon, in which he plays bass and shares lead vocal duties with guitarist Brent Hinds and drummer Brann Dailor.
Document 2: Chuck Schuldiner: Charles Michael Schuldiner (May 13, 1967 – December 13, 2001) was an American singer, songwriter, and guitarist. He founded the pioneering band Death in 1983. Schuldiner is often referred to as "The Godfather of Death metal",
Document 3: Lee Jun-ho (singer): Lee Jun-ho (; born January 25, 1990), simply known as Junho, is a South Korean singer-songwriter, dancer and actor. He is a member of the South Korean boy band 2PM.
Document 4: Suho: Kim Jun-myeon (born (1991--) 22, 1991 ), better known by his stage name Suho (meaning "guardian" in Korean), is a South Korean singer and actor. He is a member and leader of the South Korean-Chinese boy group EXO and its sub-unit EXO-K.
Document 5: Obituary (band): Obituary is an American death metal band formed in October 1984 in Tampa, Florida. Initially called Executioner, the band changed their name to Xecutioner in 1986 to avoid confusion with the thrash metal band Executioner from Boston, and then changed their name once again to Obituary in 1988. The band's current lineup consists of vocalist John Tardy, lead guitarist Kenny Andrews, rhythm guitarist Trevor Peres, bassist Terry Butler, and drummer Donald Tardy. Obituary has gone through several lineup changes, with Peres and the Tardy brothers being the only constant members. The band was a fundamental act in the development of death metal music, and is one of the most successful death metal bands of all time. To date, Obituary has released ten studio albums, and with the exception of their 1997–2003 split, they continue to perform live around the world.
Document 6: Jacque Alexander Tardy: Jacque Alexander Tardy (1767 – June 15, 1827) better known as "Tardy the Pirate", (a.k.a. John Tardy or John Late) was an unsuccessful and atypical pirate who usually poisoned his victims.
Document 7: Jun. K: Kim Min-jun (; born January 15, 1988), better known by his stage name Jun. K, is a South Korean singer, songwriter, record producer, rapper, dancer and actor. He is the main vocalist of 2PM.
Document 8: John Tardy: John Tardy (born March 15, 1968) is an American vocalist best known for his work with the death metal band Obituary and Tardy Brothers. He is the brother of Donald Tardy who is the drummer of Obituary.
Document 9: Lee Tae-min: Lee Tae-min (born July 18, 1993), better known by the mononym Taemin, is a South Korean singer and actor. He debuted as a vocalist of the group Shinee in May 2008 under S.M. Entertainment. He began his acting career in 2009 with MBC's comedy "Tae Hee, Hye Kyo, Ji Hyun" as Junsu.
Document 10: Donald Tardy: Donald 'DT' Tardy (born January 28, 1970) is the drummer of death metal band Obituary and the brother of John Tardy, who is the lead singer of the band. Besides Obituary, they have a band called Tardy Brothers, where, as primary songwriter and engineer, Donald also plays guitar and bass, as well as drums. Donald also played drums for Andrew W.K on the album I Get Wet and was Andrew W.K.'s first touring drummer who also assisted with assembling the original Andrew W.K. lineup.
Document 11: Johnny Van Zant: John Roy "Johnny" Van Zant (born February 27, 1959) is an American musician and the current lead vocalist of Southern rock band Lynyrd Skynyrd. He is the younger brother of the late Lynyrd Skynyrd co-founder and former lead vocalist Ronnie Van Zant, and of the 38 Special founder, Donnie Van Zant.
Document 12: Donnie Van Zant: Donald Newton "Donnie" Van Zant (born June 11, 1952, in Jacksonville, Florida) is an American rock vocalist/guitarist. He is best known for being a member of the band 38 Special, from its formation in 1974 until 2013. He is the middle of three brothers: his older brother Ronnie was the original lead singer for Lynyrd Skynyrd who died in a 1977 plane crash in Mississippi along with five other members and associates of the band; his younger brother Johnny is the current Lynyrd Skynyrd's lead singer since 1987. Donnie and Johnny also perform together from time to time as the group Van Zant.
Document 13: Kim Jong-hyun (singer): Kim Jong-hyun (born April 8, 1990), better known by the mononym Jonghyun, is a South Korean singer-songwriter, and radio host. He is a vocalist of the South Korean boy group Shinee, and has further participated in S.M. Entertainment's project group S.M. The Ballad. Jonghyun debuted as a solo artist on January 12, 2015, with his first EP, titled "Base". In the same year, on September 17, Jonghyun released a compilation album, "Story Op.1". On May 24, 2016, Jonghyun released his first studio album, "She Is", followed by his second compilation album, "Story Op.2" on April 24, 2017.
Document 14: Rain (entertainer): Jung Ji-hoon (, born June 25, 1982), better known by his stage name Rain (Korean 비 IPA ['piː]), is a South Korean singer-songwriter, actor, and music producer.
Document 15: Park Jin-young: Park Jin-young (born December 13, 1971), better known by his stage name J. Y. Park or JYP, is a South Korean singer-songwriter, record producer, reality television judge and record executive. Beginning as a singer, he then went behind the scenes as a record producer and eventually a record executive. He is the principal founder and chief executive officer of his own entertainment company JYP Entertainment.
ground_truth: yes