Found them!

The toothy yellow zucchini mushrooms, that is.

Former mystery mushroom.

I had moved on to process another batch of mushroom photos from the same campsite, some distance away; quite different mushrooms, I thought.

One of the club mushroom family; looks like a funnel or a vase.

This one was a good 6 inches tall, the tallest of a clump of similar mushrooms. And, looking at the group photos I had, I discovered some of the yellow toothy ones in the background.

See it there, hiding in the centre, by the rotting log? And a slightly bigger one, on the far right?

So the mystery is solved. The yellow zucchini with teeth is a youngster, a Turbinellus floccosus, aka Gomphus floccosus, aka Cantharellus floccosus. (Everyone's agreed on the floccosus, at least.)

I found a photo by Tim Wheeler, identified as T. floccosus and with the young ones present, matching mine, here. And here's a youngster in E-Flora BC. The photographer took a series of photos of the same mushroom; here it is as an adult.

Same group of mushrooms, moving to the right.

These grow up to about 8 inches high. Although they look like the edible Chantarelles and the delicious Clavariadelphus truncatus, they have no distinctive taste, and cause digestive upset and liver damage to some people. We didn't attempt to taste them. Better safe than sorry.

Where we found these.

GPS coordinates: 49.91553, -126.62502