So just to update this post... I have no idea why my LBS thought this was so difficult or why there would've been so much trial and error in finding the correct skewer with threaded nut. I literally googled "12x142 skewer with nut", bought whatever the first link was and sure enough it worked. Maybe I got lucky? I don't know but I don't feel like this should've taken three days before they told me they couldn't figure out which skewer would work. Again, I've never personally built a bike so I could be very wrong.

Anyways, bike should be done soon. Need rear brake line internally routed, saddle and grips then it's all set. will post final pics and specs (including which mysterious rear skewer I went with) sometime this week, until then it's time to learn about saddles...

So my frame is pretty much built except my LBS is confused as to what rear skewer to use. The rear axle is 142x12 and I couldn't find much on the forums about rear skewers. Any help would be appreciated!