There is a trove of independent historic stories and tales about child sacrifice in Carthage from Plutarch, Plato and even the Bible. In some sense I think it would more obvious than not to assume that child sacrifice did take place.
That sort of evidence isn’t nothing, but _in itself_ you probably need to be very careful with it.
The Greeks had no issue describing the bizarre Etruscan custom of no exposing “excess” female infants and treating the more or less equally to boys.
Killing infants or even young children was really not a big deal in the ancient word. Viewing it as some act of extreme evil is mainly a Christian thing…
Why? That’s more evidence than we have for many other things we ‘know’ about the ancient world. We often have just a single source written down by somebody less reliable than Plutarch or Plato.
I mean we’d find something corroborated by two ancients authors sufficient for most other events which weren’t as controversial (purely from a modern perspective)
"In some cases, however, the inscriptions make explicit reference to human victims, with expressions such as »zrm»ˇs(t), (a person who has not yet reached maturity) and mlk b–l (an offering of a citizen); in the Hellenistic period the phrase mlk »dm (human offering) is found. An interpretation of these construct phrases as ‘offering by a citizen/human’ rather than ‘offering of a citizen/human’ must be ruled out by the fact that the phrase mlk »mr is also found at both Cirta and Carthage: ‘offering of a sheep’ (Amadasi Guzzo 2007–2008: 350)."
So? Historic stories and tales from a time when those things weren't written down but handed orally from generation to generation are generally far removed from the truth.
After all, even in an age where almost everything is written down we still battle to separate baseless accusations from substantiated facts.
Why do you think they weren’t written done? Carthage and many other from which we have no surviving texts were highly literate societies and there is no reason to think that Greek or Roman historians did not use those sources.