A picture would still be really helpful. How's the soil?
I just returned from visiting in Salt Lake, and it's still warm enough there for planting but you're a little bit colder, possibly. You could try a few things to see how they do through the winter. If you mulch thickly over the root area, they may do just fine.
If you hurry, there are a lot of plants on sale right now, as the nurseries like to clear stuff out before winter. We got 50% off some pretty variegated Euonymous at Home Depot this week. Its a little more of a very low shrub than a groundcover, but might make a very nice contrast plant.
My daughter also has dogs, and planted red clover as a large scale groundcover at her previous house. It's safe for dogs and very pretty. Lush looking when it rains a lot or if you water it through the hot weather but it's drought tolerant and blooms if you don't mow it. The flowers attract butterflies.
