1) From Hadrat Mu'adh ibn Jabal (ra): Allah(swt) looks at his Creation during the night of the 15th of Shaban and he forgives all his creation except a Mushrik(associator) and a Mushahin(hater of Muslims). (Ibn Hibban, Ibn Khuzayma and Tabarani in his Al Kabir and Al Awsat). Ibn Hibban considered this riwaya to be sahih. Ibn Hajr Haytami said: Tabarani narrated this in his Mu'jam al Kabir and Al Awsat and its narrators are trustworthy. Shaykh Shu'ayb Al Arna'ut declared it to be Sahih in Al Ihsan Fi Taqrib Sahih Ibn Hibban and Shaykh Albani declared it Sahih is his Silsila al Ahadith al Sahihah. 2) From Hadrat 'Abdillah ibn 'Amr (ra): Allah(swt) looks at his creation during the night of 15th Shaban and he forgives his servants except two - a mushahin and a qatil an nafs(murderer). Musnad Ahmed and declared Sahih by Shaykh Ahmad Shakir. Declared Hasan by Shaykh Albani in his Silsila. Bazzar also narrated it and considered it Hasan. Hope that gives you your authentic hadith brother. Wasalaam.