This tradition has been transmitted by a different chain of narrators with a different wording, the last in the chain being the same narrator, (i. e. 'Abdullah b. Mughaffal), who said:

A bag containing food and fat was thrown to us. I lept forward to catch it. Then I turned round and saw (to my surprise) the Messenger of Allah (ﷺ) and I felt ashamed of my act in his presence.

حَدَّثَنَا مُحَمَّدُ بْنُ بَشَّارٍ الْعَبْدِيُّ، حَدَّثَنَا بَهْزُ بْنُ أَسَدٍ، حَدَّثَنَا شُعْبَةُ، حَدَّثَنِي حُمَيْدُ، بْنُ هِلاَلٍ قَالَ سَمِعْتُ عَبْدَ اللَّهِ بْنَ مُغَفَّلٍ، يَقُولُ رُمِيَ إِلَيْنَا جِرَابٌ فِيهِ طَعَامٌ وَشَحْمٌ يَوْمَ خَيْبَرَفَوَثَبْتُ لآخُذَهُ قَالَ فَالْتَفَتُّ فَإِذَا رَسُولُ اللَّهِ صلى الله عليه وسلم فَاسْتَحْيَيْتُ مِنْهُ ‏.‏