Leboob - remember milk is her main source of nourishment until 12 months.
When you left her for the day, did she have any milk at all?
What types of food are you offering at breakfast and lunch?
If she was hungry, she will attempt to eat what is front of her (that is the beauty about BLW), trusting her instincts.
I'd be reluctant to serve up the same food every time, she'll soon get sick of it and then refuse that.
Ensure she is offered food during the day, perhaps who ever is caring for her have a 'snack' plate of various things such as banana, grapes, pear, orange segments, boiled egg, rice crackers, cheese, triangle cheese etc then she can graze during the day, rather than have set meal times. My dd was a grazer at that age, always ate at dinner time, but during the day, there weren't many set dinners that we had, I just offered what I was eating at the time (I'm a grazer
)
As for hydration, if you are leaving expressed milk or formula, that's fine ensure carer offers it to her (again DD would refuse my milk from a bottle/cup, she just wouldn't take it so went without at that age and had a mammouth feed on my return to picking her up). Also have a sippy cup of water lying around all day, so she can access it (or the carer can offer it) and think of foods that are water based so pear, peach, cucumber etc are good, at least you know she'll get something.
Hope this helps.