Dontamo Prison housed an inmate known as Prisoner 934890. Upon Ferus Olin's arrival as his cellmate in 19 BBY, 934890 shared insights into the prison's regulations and potential hazards. Despite this guidance, he acted against his own counsel by feigning sickness to secure a transfer to the infirmary. Given that no one ever came back from that location, it's assumed that 934890 also perished there.