Well, getting the easy ones out of the way, agree with Virginia's Warbler and the woodpecker.
The flycatcher does have a somewhat long appearing bill, however, that primary projection does look awfully short. I know it is not a great field mark, but the head looks more rounded, rather than the flatter appearing Willow head. This definitely doesn't look like a Hammond's or Cordilleran. Doesn't look quite right for a Willow to me. Dusky definitely is a good bet, but how about Gray Flycatcher? (I would check eBird for likelihood in your area, but it is down for maintenance right now). Any chance you saw it do any tail bobbing?
There aren't any reports for Gray Flycatcher in the park, according to ebird and that local birding guide. No tail bobbing, but it was fairly active in low trees/brush.
EDIT: Just talked to my sister, who was birding with me when we took the photos, and she said she's positive she saw the flycatcher tail bobbing. She's actually the one who located it and called me over to photograph it while I was distracted by the Three-Toed Woodpecker. I'm not familiar with that as a field mark. Does it suggest one species (other than E. Phoebe), Guy?