There's a whole bunch of negative reviews about this and the post was very much worded to get others to join in.

Look. Let's assume everything you said is true and give you that benefit of a doubt.

You didn't come here for advice. You came for revenge. You've been working on that revenge for days. That's not right to him or to you.

It's unhealthy for you to let this consume you. For him, maybe he had a bad day. Maybe his wife died and he snapped. You leave the review and don't go back. Autistic children are not the only children they get excited in a candy shop. If there's a pattern of treating people this way you won't be the only one leaving such a review. But you're seeking to make him feel pain and hurt his livelihood. As much as you feel that urge, this is not the way. Move on from it, as this won't be the last time you interact with people who don't understand your child.