Final answer:
The provided references do not contain information about Abdullah Ibn Rawahah's opinion on Zaid's decision to send a letter to the Prophet, and thus an accurate answer cannot be provided.
Step-by-step explanation:
The provided text sources do not seem to offer specific information about Abdullah Ibn Rawahah's opinion regarding Zaid's decision to send a letter to the Prophet. Therefore, due to the lack of information on this specific issue in the reference text, I am not able to provide an accurate answer to the student's question regarding this historical event. The references included discuss various aspects of Islamic history and Muslim beliefs, such as the life of the Prophet Muhammad, his revelations, and the early Islamic community, but they do not specifically address Abdullah Ibn Rawahah's viewpoint on the matter of Zaid and the letter.