Yesterday I got somewhat lucky. Mamma's home! Even better luck... I didn't scare her away this time!
Unfortunately I still can't get a good view of her to identify her as the nest is deep enough for her to say mostly hidden and in the contrast of the sun and shade doesn't help much.
I was able to walk right by, with the dogs and she just followed me, she really wants to keep the eggs warm.
Oh, that's right! There's eggs! I saw them a few days ago. So today is quite the update.
I have a feeling that the speckled egg is an imposter egg, laid by another bird to fool the nesting mother and overtake the brood. I could be wrong, but this is actually a thing!