I have both. I'm pretty sure it's the same. I bought the snap shirt in bison and would like to get another in vias. It's very comfortable and very quiet.
Don’t know the Kenai. Love my snap shirt. It is an around town thing for me. Sleeves started pilling after two years. Makes me wonder how it would hold up in the woods.
Kenai is 30D stunner stretch (2-way), and to me a bit softer on hand. Snap shirts are 20D two way stretch fabric. Both pill, but the stunner stretch fabric is a bit more resistant to it.