Me neither. I read a couple of descriptions of striped cuckoos. None mentioned this tidbit and that made me suspicious.

On the other hand, I did find this: thenakedscientists.com/…/cuckoo-chicks-earn-their…

It includes a picture of a nest with a cuckoo chick and, although it doesn’t look like a pine cone, you can easily make out the speckled feathers. Also, the article is interesting in asserting that the cuckoos’ parasitism isn’t all bad.