Alex,Sadly, no that was not me with the flagging. I did flag the approach a couple of winters back when the area was first opening. Up Spencer Creek road to a "blue square" XC ski trail, through a small deciduous wooded area and a marsh, balance moves across the beaver dam, and up the clearcut/slide area, thru some conifers below the cliffs, and ultimately deposited at Split Rock Camp. That's my preferred approach, about 3 hours from the South Tieton Road.
Yale Preston showed me another route (before he moved to Montana) that goes up Milk Creek and follows a narrow ravine and deposits you well to the left of SRC, somewhere near the bottom of some WI4 route which I'd remember the name if I heard it. It avoids the clearcut and the beaver pond. However, this approach is bs on skis and worse on shoes, IMHO, having done it both ways. The Spencer Creek approach allows a TAM approach all the way to the blue square XC trail, and it's about 30-45 minutes to SRC from the drop-off. View's better that way, too, but you already know that.
When is your next planned excursion to Strobach, and will the TAM be employed, and can me and Cragg get in on it? I can pay my toll in beer.
Cheers,...sobo