HI! I have a picky eater too. I keep light colored karo syrup for her incase her sugar gets low. Mine also hates nutri cal- pushed it right out of her mouth when I gave it to her. Have you tried boiled chicken with the food you give her? That helps sometimes. She doesn't like the Eukanuba, that's obvious, so maybe get some samples from the companies listed in the Health and Diet section. All you have to do is email them and they'll send you some to try for free.
If she's as picky as mine, you just have to keep trying different foods till you find 1 she likes. I even crumbled her favorite treat on top her food to get her to eat. Try frozen peas, carrots, or green beans. She might like those. If she likes cheese, keep using that. I used ground up kibble under the wet food too. Cesars should be ok on it's own. Mine likes Merrik chicken and turkey/ duck flavors for wet food. You could try those. Nutri drops are good to give her if she doesn't like to eat. They promote their appetite. Holistic Tiny bites are a good kibble, they have a coating of nutra drops on them and the kibble bits are really tiny.
As for travel...when I'm alone I have a dog seat that sits high so she can see out. I got it online from Target. It looks like a huge cube that you seatbealt into place. There's a tether to attach her harness to, for safety. I haven't gone father than a 30 min. drive though, so I'm no help on a long drive.
I hope something works for you. PM if you have questions. I hope others will be here to give you more advice.