It's not her fault if the contract she signed wasn't honoured by the other participant. From what I've heard her contract stated that her remuneration was based on purely box office receipts with a stipulation of having a wide theatrical release. Generally this is considered to mean exclusive to studios but it could be defined as being released to a significant amount of studios.
Johanson has asked for a jury trial presumably because a jury would choose the accepted definition where a judge is more likely to accept a purer definition. If they do accept the generally accepted meaning then not sticking to purely cinema without renegotiating the contract they breached it. In short it sounds to me like her attorney made a decent contract that protected her from being cheated from a split release and instead it was the Disney attorneys who made a mistake (banking on being able to sell a different definition)