Having run this loop (unsupported), I have been unable to find any record of an FKT for the route, so I thought I would report it. In Backpacker Magazine's "Trekking Washington," published by Mountaineer Books, the route is dubbed "The Grand Loop."
ROUTE: West from Deer Park to Obstruction Point; South over Grand Pass, Cameron Pass, and Lost Pass; East along the Dosewallips River; North over Gray Wolf Pass and up the Gray Wolf River; and North-East up the Three-Forks Trail back to Deer Park.
DISTANCE: 44.4 miles
GAIN: 14,124 ft
DATE/ TIME: September 10, 2017 in 14 hours, 8 minutes, 40 seconds