The defendant is on social security disability only. Her criminal charge for $5000 is against her. Does she have to pay?

Criminal charge for what? Most likely she will have to pay the fine for something criminal.

Yes she has to pay if the court says so. Either with jail time or if she were smart a plea agreement and payment plan. Hope she has a lawyer. If not, ask the court to appoint one. If she has already gone to court, then all of this has been explained already.

Please clarify as the devil is in the details.

(Being ordered to pay and being able to collect are two different things)