My dog won’t pee outside

Okay this may sound weird but hear me out.

I rescued my little girl in August of 2024. Before that, she lived in a killing shelter in Bosnia. She’s 2 1/2 years old now.

Ever since we got her, she’s been the happiest dog as long as we’re at home. She sleeps right next to me every night, plays and runs in the Garden. But as soon as we go outside, that dog is TERRIFIED. She shivers and wants to go inside or into the Garden again immediately.

She goes potty in the garden, leading to burnt patches in our lawn. We wanted to train her to go Potty outside. We tried everything. We also have a dog trainer and tried everything she recommended.

Now I‘m asking myself, should I continue trying to force her to pee outside, or should I just let her be? When we’re on walks somewhere quiet, we live in the country, she enjoys it. But she never goes potty.

Would appreciate all of your opinions. Thanks for reading