Grading: This chain is "sahih" by way of Bishr bin Bakr, and "da'if" (weak) by way of Ayyub bin Suwayd.
Technical note / Defect ('illah): Al-Awza'i (in the chain) is "Abd al-Rahman bin 'Amr". Al-Hafiz Ibn Hajar said in "al-Fath" (8/ 125): It is a weighty hadith, and it has been criticised with a defect that is not damaging (qadih).

Reference / Source: Ibn Hibban (7219) narrated it from Wasif bin Abd Allah al-Hafiz, from al-Rabi' bin Sulayman al-Muradi, from Bishr bin Bakr, with this chain.

Reference / Source: Ibn Majah (2045) narrated it via al-Walid bin Muslim, who said: al-Awza'i narrated to us, from 'Ata', from Ibn 'Abbas. He dropped "'Ubayd bin 'Umayr" from the chain.
Technical note / Defect ('illah): Al-Walid is known for "tadlis al-taswiyah", as al-Busiri said in "Misbah al-Zujajah" (728), adding that it is not unlikely that this omission was al-Walid's doing. Al-Hafiz Ibn Hajar stated this with certainty in "Takhrij Ahadith Mukhtasar Ibn al-Hajib" (1/ 510).

General principle: Abu al-'Abbas al-Qurtubi says in "al-Mufhim" (7/ 322), explaining this hadith: It means that the sin of that has been lifted, and there is no disagreement that the sin is lifted. The disagreement concerns the rulings that follow from it: are they also lifted so that nothing is binding, or are all its rulings binding? There is disagreement about this. The correct view is that it varies according to the case. One category is not dropped because of error and forgetfulness, by agreement, such as liabilities for damages, blood-money and prayers. Another category is dropped by agreement, such as retaliation (qisas) and uttering a word of disbelief, and the like. And a third category is disputed; its forms are countless, and their details are known in the branches of jurisprudence (furu').