I think you already know the answer to your question ...

Your dog is getting treats, canned cat food, different varieties of canned dog food ... I would say she knows that if she doesn't eat what's in her bowl in a certain amount of time, you will give her something different. Dogs are very smart - she has you well trained.

I have boarded, rescued, fostered many, many dogs over the years where the owners swore the dog simply would not eat dry food, would not eat this, would only eat that, etc. Guess what ... without fail, every single one of them ate what I fed them. Not the first day, maybe, or the second or third ... but they all learned that what was in the bowl was dinner, and it wasn't changing.

As for your cat's food, put it up on the counter or another high place that the cat's can jump to but the dogs cannot.