What did we do wrong? (Raw diet question)?

Ok, if a good number of you have been reading my most recent questions (not really recent, but whatever) then you know how I was begging my Grandmother to feed my new dog im getting soon raw! Well, she got a little convinced and said that we could try my sister's chihuahua(7 pound chihuahua) on raw for 1 week (told her it takes about 5 weeks to completely get the dog used to EVERYTHING associated with raw diet, no real exceptions!) well, she thought that was too long to wait. We went to our nearby Bi Lo and got 1 small pack of bone-in chicken thighs (grandmother thought chihuahua would HATE bones, but I proved her wrong by SNEAKING a piece of the bone outside after we got home, Roxie (chihuahua) DEVOURED IT!!! We also got 1 pack of chicken liver and 1 BIG slice of this cheap beef meat (grandmother insisted we get her this $10 Fillet mignon thing but it had this herb mix on it so I clearly told her we could only feed her PLAIN meat, no seasonings, flavorings, dyes, etc. (she got worried Roxie wouldn't like it "bland' because normally we would feed her steak if we had it for dinner, made her stomach upset but nanny insisted!) but I got her to get the, as she calls it, "bland" meat! We got home and I started cutting the meat off the bone, we also got a can of pureed pumpkin! Well, nanny told me to cut up a LITTLE bit of organ meat and mix it with everything (her version of a LITTLE bit is like 1/2 a piece!) We fed her the first time, she DEVOURED it!!!! BUT, after about 3 days, I got back from school and nanny "said" that Roxie wouldn't TOUCH her food, that she nudged the organ out of the way with her nose then only ate 1 piece of the beef and didn't touch it again!!!! What happened?!?!?!?! We now have her on her old DOG FOOD (1/4 pouch of Pedigree Little Champions GROSS!!!! Do you think she lied just to get Roxie back on regular dog food or do you think this REALLY happened? Please no rude comments, my nanny wont let me feed my soon dog raw because it made Roxie "upset." I think she just didn't wanna feed her raw, neither her nor my sister wanted to! Thanks!