So ... this is what I did.
The "too religious" comment was the first one that was said to me personally and that I could say anything without feeling like a busybody. It wouldn't matter if she wasn't, but it just so happens that another coworker, one I really love, just happens to also sit very nearby and is "very religious." I told him, "You should probably turn around and not talk like that."
After the work order thing, I honestly just sat there stunned for a second. Apparently I had missed the first part of that, where he was on the phone with an HOA contact and was getting frustrated with them because they were elderly and having trouble understanding him. That's just not going to get you far anyway - do you know how many older people are HOA presidents and treasurers? A lot. And we deal with them a lot. So that lead into the comment he made to me about betting one of our account managers speaks English. At that point I really wasn't sure where to go with this, so -- and I swear I wasn't gossipping here, and the person I talked to knows that, too -- I talked to the long-time coworker (CW) on the other side of Dude. Maybe I had heard wrong, you know? Maybe ... I don't know, I was really just hoping I was wrong. I was not. This guy had mamaged to disparage old people, religious people, black people, Polish people, and random Asians in the span of a few days. The two of us decided to take it up with our supervisor.
I emailed Sup and told him that CW and I would like to speak to him privately, and that a conference room would be best. To my surprise he scheduled a meeting for that afternoon. I am very glad I talked to CW. We have both been with the company a long time, but while I can be a little bit of a firecracker she is about as reliable and calm as people come. We laid it out for him, he listened. It was kind of funny to see my normally unflappable boss look a little shocked. He said he would dig a little further, and thanks for letting him know.
Surprisingly, Dude was still at work the next day. Not only was he at work, but he had gotten a call for an interview

That turned out to be a matter of miscommunication. CW gave Boss the heads up and Boss said, "That's not going to happen. Keep it on the QT. I will take care of this." And he did. The next day Dude was gone, CW and I were informed we could tell people he wouldn't be back and to be discreet. Now, CW and i are the only permanent people in our section of the room, and we were to either side of Dude - so we were the ones to naturally say something and the ones that would work with him if he had issues. I am really really glad we said something because two other people afterward told me he had been saying some things that were just not cool.
So ... that's it. He's gone. I don't think Boss thinks we are mean or dramatic for bringing it up with him, and i think some of our other long-time temps were relieved. Peace and tranquility and innapropriate humor were been restored, at least temporarily.