Workplace injury advice

This may be a little long winded but here goes. A family member was recently injured at work. It's taken surgery, plates, pins and rehab to get them almost functional again. They are looking to be released back to work soon, which is awesome! However, what caused them to get hurt in the first place hasn't been fixed. They are nervous about going back because of this. The same thing that caused their injuries has also almost happened to their other coworkers as well. Could they report the company for not fixing the issue? Could they refuse to go back and still keep their employment until it's fixed? I feel like as much money as the company has spent for them being out of work they would have taken the situation more seriously, not just for my family member, but for all the other employees as well. they're worried about being reinjured or retaliated against if they say anything. Any advice really helps!