There is unlikely to be religious preaching on here. There is a forum for religious talk elsewhere on here that one can talk religion, so I think you'll be fine.
I would wonder what the necessity would be for you to be around to watch your wife and her boyfriend? If its not working any more, don't do it. Sometimes its fun to start out, or even helps, but usually the dynamic changes at some point. Maybe its time to chamge it up and have separate dates that are more organized in terms of time spent together in order to keep the connection with one another. That will be what rides you out for the long haul, not sex together I would think.
Question- why polyandry? Are you both married to her? Just wondering.
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