Three of Ahmet Bozoglan’s fellow Uyghur inmates are likely to face persecution after being repatriated.
Camps, a crematorium, and a corridor for expediting organ transport appear to be part of a local system.
The letter comes as MPs call on the UK to mull sanctions for Chinese officials and entities in the region.
Observers say the facility may be used to cover up wrongful deaths in the camps.
Dawut, a scholar of Uyghur cultural traditions, disappeared in 2017 and is believed held in one of China's many political re-education camps in the Xinjiang Uyghur Autonomous Region.
The series about Sultan Suleiman was seen to promote ethnic identity amongst Turkic Uyghurs.
The legal resident of Turkey became stranded amid coronavirus restrictions while on pilgrimage.
The parliamentarians say the court should agree to investigate a complaint filed in July.
Emma Reilly says OHCHR has been doing so for years, putting participants and their families at risk.
The act lifts an 18-year designation that many say was made in error in the wake of the Sept. 11 attack.
Yusufjan Amet said he had monitored the Uyghur exile community for years before speaking out.
Kastar Polat was handed a 15-year sentence and a hefty fine for posting the song to social media.
Another five have been sentenced to prison, while others are forced to work in factories or missing.
Söyüngül Chanisheff recalls her years in prison after working towards a Uyghur state in the 1960s.
Nothing has been heard about the three men believed to have been sent back to China in September amid fears they may have been harshly treated or killed on their return.
The designation would allow Washington to coordinate an international effort to intervene.
The cases have thrown the city into a lockdown with mandatory testing of millions.
They say that the heightened risk of persecution Uyghurs face requires greater US protection.
