Even if illegal immigrants receive these pamphlets encouraging them to vote they still won't be able to, because they won't be registered. And obviously they can't register without valid proof of citizenship.
Everyone gets spammed with these voting materials before elections based on old and inaccurate information - usually from the last person registered at the mailing address.
Illegal immigrants committing voter fraud has been investigated many times before. Trump's recent voter fraud commission had to be almost immediately disbanded because it
found no evidence to support its existence.