Given that they caught this guy by faking a call for help from his men, it's worth considering that he was an officer willing to go to the relief of his men - so one of the 'good' ones. It also seems that Rus officers might be less willing to respond to calls for help going forward. Then there's the information he's providing.

Seems like a triple win: Rus down one of their good guys, officers now even less likely to respond to troops in trouble, troop positional info.

The Rus have probably shifted forces since he was captured, but neither terrain nor trenches can be moved.

Just thinking it through...

Edit: I wouldn't put it past the Rus to take this out on his family. They had a habit of doing that in WWII, and the culture doesn't seem to have changed.