The smoothing groups seem to be set up wrong. I'd suggest removing any smoothing groups on the sides. Especially noticable on the third image. Here's the Polycount wiki page on the topic http://wiki.polycount.com/wiki/Smoothing_Groups
To make it clear, you can use smoothing groups on non rigged meshes: https://developer.valvesoftware.com/wiki/Smoothing_groups https://developer.valvesoftware.com/wiki/Hammer_Smoothing_Groups_Dialog An another page there mentioning that rigged assets will have 1 smoothing group though, but I'm not a source engine user so I…
http://wiki.polycount.com/SmoothingGroups Specifically, look at the text on the left of the image that talks about normals. That explains what soft edges from smoothing groups does.