Although the original manuscript is not very clear here, the reading appears to be the plural traditions. When Oliver Cowdery was copying the text from 𝓞 into 𝓟, he initially wrote the singular tradition, but then soon thereafter he inserted the plural s at the end of tradition. The question of tradition versus traditions is discussed under Mosiah 1:5. For each case of tradition(s), the critical text will follow the earliest textual sources, thus traditions here in Alma 19:14. Also see the discussion under Alma 21:17 for a list of all cases of the expression “tradition(s) of one’s fathers”.
Summary: Retain in Alma 19:14 the original plural reading traditions, as it apparently reads in the original manuscript.