In some cases an employer may argue that the employee was not actually injured on the job, but rather was injured elsewhere and is claiming the injury happened on the job. The attorney can gather witnesses, get the right type of medical reports as well as present the evidence that will clarify where and how the injury occurred.
In some cases there is a settlement or hearing, and the insurance company has agreed to a repayment or compensation. However, you may find you are not getting paid, despite the agreement. A worker compensation attorney will fight for you to ensure that the contract is upheld and you receive your payments.