Retraining older dog to potty outside has gone horribly wrong. I don’t know what else to do. Parent is threatening to get rid of her. Please help!

This is my first Reddit post, so i hope I’m doing this right. Also I’m sorry if this is long, i wanted to make sure i gave all the info.

I have 10 year old female toy poodle. She was pee pad trained for 9 years, but since she likes to eat her poop she would often hide and poop elsewhere in the house. I’ve tried giving her supplements to where she wouldn’t want to eat it, nothing stopped her. Around March of last year, my mom got fed up with her going in the house and decided we needed to retrain her to go outside. I should clarify that she is very much my dog, so I am the one caring for her primarily. It’s now January and she still is not trained to go outside. I got a bell for the door, she refuses to ring it to signal she needs to go, in fact she gives me zero signals. I try to take her out often and at consistent times. She gets rewarded with a treat when she goes outside. But she still is going in the house. To the point where I will take her out, she’ll do number one and two, but then immediately poop in the house after. I’ve tried multiple pet smell remover sprays so that she’s not marking her scent. When she goes potty inside I immediately take her outside to reinforce where’s she’s supposed to go. My mom is threatening to git rid of my dog now. I struggle with depression, and the threats are effecting me emotionally. My dog is very much my support animal. My mom has tried spanking her when she does this, but it hasn’t made a difference. Plus it upsets me as I don’t believe in hitting dogs. It is becoming an every day issue. I am desperate for help! Any advice is welcomed. What am I doing wrong?