Are chicken livers safe to eat cooked slightly pink? Is "chopped liver" safe when using schmaltz as an ingredient?
That depends. What does the texture of the inside pink portion look like? Does it still look like it's raw liver? Or does it look and have the texture of the rest of the cooked liver, but slightly pink? If the latter, it is probably safe to eat.
The pink colour in meat is given by myoglobin. When myoglobin is heated it loses its structure and changes colour, which is how many people tell doneness.
However, you're talking about the liver, which contains a lot more myoglobin than normal cuts of meat, and even after cooking may have residual myoglobin that hasn't been denatured.
Here's a thread with more discussion on the topic of cooking chicken livers for pate (which seems to be what you're doing)
As for your second question, I don't see why using schmaltz would make your chopped liver unsafe. Are you worried about the salmonella? Schmaltz is fat that has been already rendered, so any germs it contains would likely already have been killed off, and as long as it was stored properly there should be no problems with food safety.