Welcome to YT!! I have had dogs that go through finiky stages, but mainly just a cat. I tend to agree with the advice you got with inadvertently encouraging the pickiness by switching foods. Usually, as long as they're not starving, I can wait them out, and then they start eating fine again. But it's never been anything really serious or long.
Hopefully, someone will have some better experience for you.
But Welcome to you and Dolce. Can't wait to learn more about her and see some pictures.