Assalaamu `Alaykum,
Nader, as you may have guessed, when a contemporary of the Prophet (salalahu alaihi wa salam) narrates from him with a clear seeghat sama'a, it is accepted that this person is a sahabi if the chain up to him is authentic. Please refer to Al-Isaba where Ibn Hajar discusses this issue and its relevance to Ibn Abi Umaira.
Correct, I have read Ibn Hajar's discussion in his al-Isaabah. My issue is this:
1.) This narration according to Ibn Abi Hatim is not seeghah sama`ah (I heard the Messenger of Allah), rather it is "The Messenger of Allah said"
2.) The other narration of Ibn Abi `Umayrah that has Seeghah sama`ah is not authentic because we do not know the Shaykh of al-Walid b. Muslim
وقال ابْنُ سَعْدٍ: روَى الوليد بن مسلم،
عن شيخ من أهل دمشق، عن يونس بن ميسرة بن حَلْبَس: سمعتُ عبد الرحمن بن أبي عَمِيرة المزني يقول: سمعت رسولَ الله صَلَّى الله عليه وسلم يقول: "يَكُونُ فِي بَيْتِ الْمَقْدِسِ بَيْعَة هُدًى"(*).
3.) All other hadith from Ibn Abi `Umayrah have the wording "The Messenger of Allah said" without any seeghat sama`ah.
The first narration which would be Sahih (according to the majority) has seeghat sama`ah, but as Ibn Abi Hatim says that Ibn Abi `Umayrah did not hear this particular hadith, rather it should be "The Messenger of Allah said".
The Second narration which has seeghat sama`ah is weak due to the unknown person in the chain from al-Walid b. Muslim.
The other narrations do not have Seeghat sama`ah.
If the above is the case, then what grounds do we have that he was a Sahabah, other than peoples statements of him being one? I believe his Suhbah could still be questioned if we analyze the hadith that the scholars are using to prove his suhbah. I believe this is how Ibn `Abd al-Barr analyzed the situation, unfortunately, I believe scholars dismissed his opinion because they believed that he misunderstood Ibn Abi Hatim's statement.
Wallaahu A`lim.
Wa `Alaykum Assalaam