It is easy to say other people should martyr themselves for the cause. It is mach more difficult to be so idealistic when it is your freedom and livelihood in question. I think he did the right thing for himself and his family. There is no shame in that.
It easier to say such things when your own life is not on the line; however, it is no less true but every time someone pleads guilty to a crime they did not commit the world dies a little.
That is the sad truth of the world we live in. My grandfather used to tell me to pick my battles and to make sure they are worth fighting. This kind of battle just isn't worth the risk. I understand and agree with your stance on this in principle, but losing your loved ones and freedom for what could be decades is a really high price to pay.