Musāfir, or someone further down the chain, for it is not permissible to add to a narration on the basis of personal opinion without making this clear; otherwise, it would undermine confidence in the hadiths of trustworthy narrators, as is obvious.
There are other corroborating reports, but those already cited suffice. All of them agree that the preserved wording in al-Zuhrī’s narration from Anas is: “a silver ring.” This is problematic, for the preserved version of this account in the hadith of Ibn ʿUmar—narrated from him by Nāfiʿ and ʿAbd Allāh ibn Dīnār—is that the ring discarded by the Prophet, and by the people, was a gold ring. It was regarding this that he said: “I shall never wear it again.” It was narrated by al-Bukhārī, Muslim, and others, and is documented in Mukhtaṣar al-Shamāʾil (63/84).
For this reason, Ibn ʿAbd al-Barr said in al-Tamhīd (17/100), after this hadith of al-Zuhrī: “This is an error according to the scholars; what is known is that he discarded only a gold ring, not a silver one.” He then said: “What is preserved in this chapter from Anas differs from what Ibn Shihāb said; a group of Anas’s students narrated it from him, and we have mentioned some of them.”
Al-Ḥāfiẓ likewise stated something similar in al-Fatḥ (10/320), saying: “Al-Nawawī said, following ʿIyāḍ: All the hadith scholars said that this was an error on the part of Ibn Shihāb, because the discarded ring was none other than the gold ring. Some of them interpreted it otherwise, as will be mentioned.” He then cited some interpretations whose forced nature is evident. No one after the Messenger of Allah is infallible; and once the hadith scholars have judged Ibn Shihāb to have erred, there is no justification for such interpretation.