@mikesull I posted recently about my finicky eater (at 12 weeks old). I was willing to try anything because she was getting bigger yet losing weight. When ribs start showing on a puppy it's not good, imo. Things have turned around for us. I started feeding raw which she would mostly eat (chicken w/ veggies preferred). She walked away from raw turkey/beef heart.
I was hard core about timing. MY timing. I learned in the last couple weeks - leave the fixed portion down for her to eat when she was ready. It worked. Mixed in kibble slowly. Her eating habit is to eat 10% now, 50% 30 minutes later, the rest in the next hour. Fine. She ate. She gained weight. Now I mix in chicken broth (Petco's Petcoach that looks more like human chicken stew) with Honest Kitchen kibble and we're good! I will start making my own cooked "stew" for cost and convenience and freeze in small portions.
The lesson for me is to let go of hardcore pedantic methods. I will probably never "free feed" but this puppy eats on a different schedule than any other dog/puppy I have ever cared for. This schedule works for us.