The whole premise is absurd, you can't even suspend your disbelief.
Why you would ever defend a war criminal if the cost would be to loose more of your own people. Especialy this individual is not even having any special strategic or tactical importance.
Even if you would be victorious in the fight you would lose some of your men. Save 1 and spend 10 if you are victorious, or if you loose you get everybody killed some 200-300.
By the way: what kind of siege is this when you can sneak at will in and out of the besieged camp? That could be possible only if the grounders do not have enought numbers to mantain a proper siege at withch poin you have to ask: how could they ever defeat people armed with fire arms?
By the way: what kind of siege is this when you can sneak at will in and out of the besieged camp? That could be possible only if the grounders do not have enought numbers to mantain a proper siege at withch poin you have to ask: how could they ever defeat people armed with fire arms?