If the talented voleyball player were to accept the revised terms, she could sign the scholarship offer today.
"Were to" is generally used to highlight that the conditional form that has been used presents a hypothetical situation that is highly unlikely to happen. Therefore, "were to" emphasizes the improbability of the condition. In the case of this specific sentence, it is unlikely that the talented voleyball player will accept the revised terms and; therefore, sign the scholarship offer today.