Ammon does record Limhi describing his people's relationship to Noah and the death of Abinadi (Mosiah 7:25-28) but does not mention Alma specifically. Nevertheless, Limhi would surely have discussed that aspect of Abinadi's mission as it is clearly important to Limhi. Just how important Alma is to Limhi is evidence in the last part of the verse. While these are Mormon's words, we may easily suppose that they accurately echo the original in describing Alma, "who had formed a church of God through the strength and power of God."
Limhi's people in their humble state would certainly have recognized the truth of Abinadi's teachings (since his predictions about the Limhites had come true, surely Abinadi was also correct about the nature of the atoning Messiah). They also would have known of Alma and those who went with him. Apparently that knowledge also included information about Alma's "church" and his ordinance of baptism, as we will see in verse 33.