You might be aware of this as a Virginian, but roughly a year and a half ago (perhaps a bit less), there was a suicide at MCB Quantico. It was a BIG deal. Commanders at Quantico, and throughout the military's stockade and brig system, are now especially cautious because of it.
Manning, to compound matters, had already exhibited symptoms of psychological and psychiatric stress before the Wikileaks scandal. In fact, Manning was facing possible administrative separation because of it. Had Manning even been able to attempt suicide, to say nothing of committing suicide, officers at the highest level would have been relieved. They are being appropriately cautious here.
Had Manning succeeded, they all should have been given medals.