This hadith has been narrated on the authority of Zuhri with the same chain of transmitters that a person broke fast in Ramadan whereupon the Messenger of Allah (ﷺ) commanded him to free a slave (as an atonement), and the rest of the hadith is the same as narrated by Ibn Uyaina.

وَحَدَّثَنَا مُحَمَّدُ بْنُ رَافِعٍ، حَدَّثَنَا إِسْحَاقُ بْنُ عِيسَى، أَخْبَرَنَا مَالِكٌ، عَنِ الزُّهْرِيِّ، بِهَذَا الإِسْنَادِ أَنَّ رَجُلاً، أَفْطَرَ فِي رَمَضَانَ فَأَمَرَهُ رَسُولُ اللَّهِ صلى الله عليه وسلم أَنْ يُكَفِّرَ بِعِتْقِ رَقَبَةٍ ‏.‏ ثُمَّ ذَكَرَ بِمِثْلِ حَدِيثِ ابْنِ عُيَيْنَةَ ‏.‏