Firstly, regarding his unethical behaviors: (!!!!)
And I'm in agreement with BeyondtheRainbow's advice.

In terms of potential action(s), I think reporting him might not be a bad idea. On the things not related to you (Because it doesn't seem like it would fall within ADA parameters. And it would require a lot more personal involvement that might not even be worth it.)

If you do decide to report the unethical things, personally I'd wait awhile. Why? Because it gives you more time to reflect on it and the reasoning behind any action. Also, it separates you from it. To immediately act, it'd be pretty obvious it was you, and might well come off as knee-jerk retaliation. Which, even if it was all about revenge, you don't need it to look like that.

Does that seem a little devious? Well, yes, a bit. But also no. If the recipient saw this simply as revenge, they might not take it as much to heart as it should be. That time separation makes the wrong-doing a starkly stand alone issue.