Yang Yi was still in great danger, but his peril also protected him.
For spies, there was never any courtesy to begin with. If it weren't for the fact that Yang Yi had yet to recuperate and even the slightest movement could kill him, Gary Keene wouldn't have been so polite in speaking to him.
Truth Serum, various imaginable and unimaginable brutal tortures would have been used on Yang Yi; this was the proper interrogation mode for a spy. Yang Yi had yet to endure such treatment purely because any contact might result in his death.
Even if Yang Yi cooperated, once his health improved somewhat, MI5 would repeat every method of torture on him and torment him to the point of near death, then revive him, only to interrogate him many times over before they might start to believe his testimony.
