The turtles should consume virtually all of the things that you mentioned. The Red-eared should consume more of the plant matter, and the Western Ponds should consume more of the animal matter.
The problem is, you've taken adult turtles out of the wild. These turtles are probably frightened and upset that they now live in a habitat that is only a fraction of where they used to roam free. Your Red-eared will probably adapt. However, Western Pond turtles are notoriously difficult to acclimate to captivity. Not to mention, they're highly protected from collection in virtually every State where they're found. Many, if not all, or your Western Pond turtles will probably die if kept. They should be released where they were caught immediately. Contact some Western Pond breeders to learn how truly difficult the adults are to acclimate. California allows some turtles to be adopted out (confiscated, unreleaseable, and/or rescued animals). Success rates are terrible even for the most experienced keepers.
You've done a service to that ecosystem by removing the Red-eared Slider. Sliders are not native to any habitat where Western Pond turtles are found. Do not release that Red-eared Slider! Construct a fenced-in outdoor pond if you can. Provide plenty of basking and hiding spots. Plant it heavily with non-toxic plants and it should adapt well to captivity. Feed it dark, leafy greens, hibiscus leaves and flowers, sweet potato, apple slices, and much much more. Offer lean meat, mazuri aquatic turtle food, trout chow, and whole fish occasionally. What your turtle needs is some time to adapt. This is fairly typical of a wild caught turtle, even if it was once a captive. If you ever decide to get rid of the turtle, adopt it to someone else. Please don't re-release it!
I'm sorry for being so candid. I hope you've found it helpful anyway.