1. antispeciesism = rejecting discrimination based solely on species membership.
2. all living beings having exactly the same moral value.
Most anti-speciesists defend (1), not (2). Anti-speciesism also doesn’t imply that killing animals is always wrong, most people instead reason in terms of reducing suffering/benefiting interests, and proportionality. You can believe a guinea worm has moral worth and still think eradicating it is justified because of the suffering it causes.And the “insects die for carrots” point is not really a problem specific to veganism, since animal agriculture typically requires even more crops, land use, and indirect animal deaths. Also there's vegans that are speciesists and anti-speciesists that aren't vegan. Those concepts intersects but are not strictly equal.
I'm not sure to understand your other points but strongly agree communication helps to grow ethics and gain empathy. However it's not absolutely required as seen with the exemples of comas, mute, newborn, or as you mentioned someone of a different culture or language. I hardly understand how is it "impossible for [the dogs] to make their preferences known" especially in the situation of being slapped. Perhaps I missed you point because that contradict all my interaction with dogs and gods's owners.