Here in the original manuscript, we have a momentary loss of that after “it came to pass”. Somewhat later, with narrower ink flow, Oliver Cowdery supralinearly supplied the that, probably when he read the text back to Joseph Smith during the dictation process. The subordinate conjunction that usually follows “it came to pass”, but not always. Since either reading is possible, there would have been little motivation here for Oliver to emend the text on his own. The critical text will therefore accept the occurrence of that after “it came to pass” in Alma 24:1. For discussion of this variation, see under 1 Nephi 7:7; also see the more general discussion under that in volume 3.
Summary: Accept in Alma 24:1 the occurrence of that (the corrected reading in 𝓞) after “it came to pass”.