I never heard KUOW on 99.5 here, so if it was on I don't know when. And regarding LPFM's, KODX-LP (which only identifies as KODX) has been testing afternoons from around noon to 6, give or take, on 96.9. Not sure they plan to carry any music; they're running Pacifica programming when they test.
I hear them well enough, but I think their service area is a bit southwest of me.
Back to the 99.5, if they were silent due to interference, I'd think it would be interference to 99.3, and I wonder if they've made facility changes to prevent that.