Saw a bunch of doe on the green diamond resource co land I was shown by an old buddy last year up in GMU 633, a bit east of lake limerick and south of mason lake is about the best I can approximate as I'm from Olympia, don't know the mason county area too intimately. I'd reckon that whole peninsula is prime if you've got a doe tag... Lot of green diamond resource co land up there that may not require their walk in permit, their permit land is documented at
https://www.greendiamond.com/recreation/rec-program/forms/N-S_Combo_map.pdf - if it's northeast of Shelton I don't think you need to buy the walk in permit. Check OnxMaps for the stuff that's northeast of shelton as there's a lot of it.
Try the areas on the edges of clearcuts that also have other terrain changes like railroads or water. That's where I saw em last year while I was walking along a railroad with my old friend last year anyway. Wish I had had a doe tag when we had come across 'em!
However: be careful not to walk ON or directly adjacent to a railroad though, stay on the forest co land if you can. I was admonished by the rail co employees that drove by on a railroad equipped truck that told me I can't be on the railroad and hunting with a gun. I learned my lesson when I went back there alone and ran the same route!