I think the Doorish route was completed by the Volken route called the Si Pillar. It was reported to me that the Doorish climb had ended on or near the ledge at the base of the upper route. Andy Dappen (Couloir Magazine) was the partner on the finished route. All descent anchors were removed. There is a topo for the route in the North Bend guide shop, but you're right about the closures of the area to development. I believe the canyon ScottP mentions is called "The Black Canyon" and can be accessed by parking just across the first bridge on the moon valley road, and hiking up the overgrown road to the base of Mt Si. From there it is a short bushwack to the talus field at the base of the canyon. Expect steep talus and dirt. At the top exit right and head high. The rock was reported as compact and required pins and some hooking moves.
Russian Butte is probably an open option with a sporty river crossing.