If I give my buttons seed - which I assume this 'finch food' is? - they prefer eating that above their game bird feed, and seed is in general too low in protein. Chick crumb is probably not above 21% protein? So that's too low as well, and I'm just guessing they are not eating much of it?
The boiled eggs probably help, depending on how often you offer it and how much they eat. But feed that spoils quickly is too much work imo. So if I were you, I'd go and buy a bag of game bird starter or similar (turkey feed might have the right amount of protein as well) with at least 24% protein and switch them to that. You might need to grind it to make it small enough for them to eat.
Is the oyster shell crushed to a size she can eat?
Another problem with seed, is that it's low in vitamin D and if she doesn't get enough of that, she can eat as much oyster shell as she can and it won't help her, as she needs the vitamin D to utilize calcium. So I'd definitely get rid of the seed. You can give a little directly on the bedding once a week or so, so they can spend some time foraging for it, but don't make it a significant part of their daily diet.