Bolder-dash writes:
Do you think this innateness arose from a chance genetic mistake?
Innateness? I don't think of innateness in the way you're using the term. Keeping this at an undetailed level, qualities are either innate or acquired.
But if I rephrase your question to be, "Do you think human empathy for other humans arose through a chance genetic mistake?", then given that all mutations are genetic copying errors, what other conclusion is there? Of course, any significant quality arises only after many mutations and generations and aided by the filtering of natural selection.
--Percy