The RR food should be fine for a treat! I have not heard of those foods causing any real problems; if that were the case, it would be all over the internet. In fact, my vet told me that for some cats, fish should be totally avoided & she has seen cats getting urinary problems from Tiki and other expensive brands because of all the seafood. That said, cats are durable and they have an excellent sense of smell that can detect more odors than dogs so they can tell the diseases in the animal used in the food. That is why cats are so "finicky" - they can smell & taste something "off" or disgusting. Too bad about your mom. I am from a strong culture and know how controlling some moms can be. After my dad died, i had to move in with my mom (she is almost 90) and gave up most of my freedoms. And if I insist on having my own life, she can be verbally cruel to my adult disabled daughter or my things will go missing or thrown away or broken. My siblings live out of state.