A second artist has decided to boycott April’s five-day Bluesfest music festival in Byron Bay, with the Zambian rapper Sampa the Great joining Melbourne rock band King Gizzard & the Lizard Wizard. The action by the artists is in protest of the Easter long weekend music festival’s inclusion of the indie rock band Sticky Fingers, whose lead singer Dylan Frost has been dogged by controversy since allegations about his behaviour arose in 2016. Festival appearances of a further four artists have been thrown into doubt after the schedule of performers released by festival organisers on Wednesday showed a number of holes in the previously advertised lineup. The Guardian has sought comment from the agents acting for US rappers Big Freedia, Talib Kweli and GZA, along with New Orleans soul band Soul Rebels, as to why they have disappeared from the lineup. Comment has also been sought from the Bluesfest director, Peter Noble. On Wednesday, Sampa the Great’s representatives told the ABC’s Double J they had been requesting festival organisers remove her name from the Bluesfest lineup since 14 February, having “started contact with Bluesfest to inform them of our standpoint within half an hour of receiving the embargoed press release and seeing the remainder of the line-up”. Earlier in the week King Gizzard & The Lizard Wizard pulled out in protest of Sticky Fingers being included, issuing a statement saying that “as a band and as human beings, we stand against misogyny, racism, transphobia and violence”. Sign up for Guardian Australia’s free morning and afternoon email newsletters for your daily news roundup “Given this decision by the festival, we have decided to cancel our appearance at Bluesfest,” the statement read. “We are deeply disappointed to be in this position but sometimes you need to be willing to make sacrifices to stand up for your values. This is, unfortunately, one of those moments.” Sticky Fingers went on a year-long hiatus after allegations surfaced in 2016 that Frost had abused and threatened the musician Thelma Plum and her boyfriend outside a Sydney hotel. Frost subsequently apologised publicly for his behaviour, citing alcohol addiction and mental health issues as contributing factors. In the same year, Frost was accused of shouting racist remarks at a gig headlined by an Indigenous punk band. He has since publicly denied these claims and was quoted in reports saying: “Rumours have been spread around suggesting that I’m racist. That is complete bullshit.” Soon after the band returned to performing, Frost was allegedly ejected from a Sydney pub after a verbal altercation with a transgender person, in which he allegedly screamed and swore at her. At the time a Sticky Fingers spokesperson did not deny Frost had been asked to leave the hotel, but denied that he had instigated the altercation or threatened violence. In a statement on Facebook in 2018, Frost wrote: “I am wholeheartedly against racism, and so is the band ... I do not condone or in any way excuse violence against women, straight up, I never have and I never will. “I also have to acknowledge that my alcoholic behaviour in the past has intimidated or made people feel unsafe around me, and I am truly sorry for this.” On Tuesday, the festival director, Noble, issued a statement directly to ticketholders, stating Bluesfest was backing Sticky Fingers in the name of “inclusivity”. “We want to support artists who are achieving greatness which often involves overcoming incredible hurdles,” the post said, adding that Sticky Fingers “aren’t monsters”. “They are a seriously great Australian band whose singer has had to overcome barriers that would have sidelined all but the most determined to continue to perform,” Noble wrote. On Monday, Noble issued a statement after King Gizzard & the Lizard Wizard pulled out, saying he respected diverse artists to exercise their freedom of artistic expression, but believed it was time to allow Sticky Fingers “a chance at rehabilitation”. “There has already been a lot of social media traffic about this decision. I think one commentator well reflects my feelings, as previously stated: ‘That whole situation happened 7 years ago and the lead singer of Sticky Fingers has been extremely apologetic and open about his bipolar schizophrenia and substance abuse during that time and is also Māori. They’ve done the work to try and make amends and took a long hiatus to fix things.’ “Forgiveness is critical to helping people with mental health challenges continue functioning in society,” Noble added. “It has been suggested that because of the listing of Sticky Fingers, Bluesfest and I endorsed the lead singer’s ancient troubled behaviour. That suggestion is deplorable, untrue, and actionable as being defamatory.” The Guardian has sought comment from Sticky Fingers’ management.