Rashid Gedel, 25, and Samuel Dodsworth, 43, are charged with murder over the alleged attack at HMP Wakefield on Saturday morning.
Emergency crews were sent to the prison in West Yorkshire, but disgraced rock star Watkins, 48, was pronounced dead at the scene.
Watkins was serving a 29-year jail sentence for child sex offences – including the attempted rape of a fan’s baby.
On Tuesday, both suspects were due to make their first appearance before a Crown Court judge.
Dodsworth appeared via video link from HMP Wakefield, but Leeds Crown Court heard Gedel, referred to as Rico Gedel during the hearing, had refused to attend remotely from the jail.
Prosecutor Tom Storey KC said: “The reason for Rico Gedel’s non-appearance this morning is said to be a refusal on his part to attend on the link. It appears he wanted to attend in person.”
No bail applications were made, and both men were remanded in custody until their next appearance at the same court for a plea and trial preparation hearing on 12 November.
Judge Guy Kearl, the Recorder of Leeds, set a provisional date of 5 May for the trial, which is expected to take two to three weeks.
Watkins was jailed for 29 years in December 2013 with a further six years on licence after admitting a string of sex offences.
The singer was arrested following the execution of a drugs warrant at his Pontypridd home in September 2012 when a large number of computers, mobile phones and storage devices were seized.
Analysis of the equipment uncovered his depraved behaviour.
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Watkins was previously taken to hospital after being attacked in 2023. At the time, police said his injuries were not believed to be life-threatening.
In 2019, he was jailed for 10 months on top of the sentence he was serving for child sex offences after he was found guilty of possessing a mobile phone in prison.
Watkins claimed two inmates forced him to hold on to the phone so they could contact women who sent him fan mail in order to use them as a “revenue stream”.
In 2014, Watkins was told he could not appeal against the length of his 29-year jail term.
