Pregnant, young sister was 2ndary lease signer, fled domestic violence, & now shows as collections for 4 months on Experian. Any way to resolve/revert credit hit?

Her ex-partner was the primary signer of the lease, which she does not have a copy of. She fled the day after he was arrested and has had no contact with the apartment. Ex is still awaiting sentencing in TX, sister is now out of that state.

Sister appealed the credit hit with experian by submitting a simple text explanation of the situation and was denied. She did this before I knew about it.

She's very young and inexperienced with finances/credit, is less than a month from due date, was laid off from her employer who closed their doors. She has no car.

Are there any means by which this credit hit can be expunged/reversed? Any sort of forgiveness plan for victims of domestic abuse or young mothers? If not, how can she best restore her credit? How would liability for the lapsed collections be split between her and an ex she no longer is in contact with for safety?

After recently learning of the situation, I told her to not contact the collections agency until we know what the best path forward is, and she has had no prior contact with the collections agency. I know it would not do any good to contact the leasing office because the debt is already in collections, but is there any feasible way of reverting this to place responsibility on the scumbag ex?

She cannot find work without a car where she is, and likely can't get a loan for a car with bad credit.