Other scientists also said the proposal looked promising but could not evaluate it fully because the details had not been published． 

本句中的but后面是不是省略了分句的主语了呢？谢谢

Other scientists also said that the proposal looked promising but they could not evaluate it fully because the details had not been published.

参考译文：其他科学家们也说，该提议看上去很有前途，但是他们不能充分评估，因为细节还没有公布。