First, he has apologized for his initial response which called me a liar, which I appreciate and shows that he actually takes the time to read responses to comments he has posted. That in itself is better than the other account that you are attempting to associate him with.
Second, the account you referred to in a previous post never did that, simply kept spewing toxicity and ignorance. If the two accounts are actually the same person (which I highly doubt), then he has started to become more open to criticism and corrections. If you hadn't come at him like toxic ass yourself, then your entire little feud probably wouldn't have happened. Don't go and start calling out others for "caustic ignorance" and "mental instability" while exhibiting the same exact traits yourself.
Now that that's been taken care of, if you would like to further debate, I would ask you politely to try to be civil while doing so. Toxicity only breeds more toxicity, as I'm sure you're well aware. Just because you can remain anonymous behind a keyboard doesn't give you the privilege to be rude as hell whenever you want. If you wouldn't talk to someone face to face like that, then don't do it online either.