Okay trying to get to the actual question, not the one(s) asked but basically the one you want an answer to.
It sounds like what is being asked is, this couple would like to find a man to date them both. Male unicorn basically, but want it put out there that there would not so much be a romantic relationship between the two men, a friendship is fine and of course sexual contact with all three. They are just unsure how to phrase it so that the man they are looking for will not assume too much in the realm of a romantic relationship with the male half of the couple. (or maybe with both halves of the couple) Am I close?
Me: Late 30s pansexual poly.
DH: My husband of 19 yrs and father of 3 teen girls.
DC: LDR of +4 year