The star witness at Kassir's trial was cooperating co-defendant James Ujaama. Ujaama initially plead guilty in Seattle, got a 2 year sentence after agreeing to cooperate for ten years, until 2013, but then fled to Belize while on supervised release to avoid having to cooperate against Abu Hamza and the others. He was caught, his plea deal was voided, and he got an additional 24 months. He then agreed to testify against Kassir and pleaded guilty to terrorism charges in New York carrying a possible 30 year sentence.
Ujaama always insisted he was not supporting al Qaeda but the Taliban. His guilty plea in Seattle was to providing material support to the Taliban, not al Qaida. Nonetheless, the government prevailed in its argument at Kassir's trial that Kassir, Abu Hamza, and Aswat conspired to support al Qaeda. (The Government's expert witness at trial was, no surprise, Doogie Howser.)
Ujaama testified at Kassir's trial that he proposed the Bly, Oregon training camp site to Abu Hamza and Kassir and Haroun Aswat flew to Oregon to train people. In addition to Ujaama's testimony on this charge, the Government produced a fax from Ujaama to Abu Hamza that Kassir had seen. The wife of the owner of the Bly, Oregon ranch also testified. The other charges involved setting up websites for promote jihad. Ujaama testified he established websites at Abu Hamza's direction. A search of Kassir's laptop revealed material that implicated him on these charges.
In 2004, Abu Hamza was charged in connection with the Bly, Oregon camp and arrested in Great Britain. He is also charged in the same case with conspiring to kill Yemen tourists in 1998.
Kassir, a naturalized Swedish citizen originally from Lebanon, was extradited from the Czech Republic in 2007. He had been arrested in Prague during a layover on a flight from Sweden to Lebanon. He has a long history of mental health issues. I doubt he would make a great witness, even if he were inclined to cooperate in exchange for greater prison privileges or a faster step-down to a less secure part of Supermax.
I haven't found any record of Ujaama being sentenced after his plea and cooperation in New York. There are reports that he won't be sentenced until his cooperation is complete, which would mean after his testimony against Abu Hamza. He is not listed as an inmate by the Bureau of Prisons under Earnest James Ujaama or James Ujaama, or by his registration number, so I assume (but do not know) that he is in the witness protection program, waiting to testify against Abu Hamza.
The trial for Abu Hamza, who has diabetes, one eye and a hook for a hand, could easily not begin before 2014. Until then, he'll be held in the maximum security unit at MCC in Manhattan.
I followed Ujaama extensively since his 2002 arrest in Denver on a material witness warrant. He was big news for a while, partly due to being related by marriage to our then-Mayor Wellington Webb. All of our coverage is accessible here.