I don't think NJ would be interested in acquiring Quinn in a trade beyond being Jack's brother. Look at NJ's recent additions on defense. Hamilton, Graves, Jaros, Siegenthaler, Hurtig, Mukhamadullin, Bahl, even Luke Hughes, are all tall and rangy. Quinn is a fantastic player, but he's not that sort of defender. NJ would likely have to move on from Ty Smith and while Quinn is certainly a more dynamic player, Smith has more developing to do and may be more well rounded a defender when all is said and done which NJ might prefer. If nothing else, I expect Smith to be less expensive than Quinn which helps as the other young players become more costly. Smith is also Jack's roommate and they are close friends.
I'm sure when the day comes that Jack and Quinn both hit UFA they will try to find a landing spot that appeals to them and will pay them. Frankly, I don't think any team is crossed off their list. My guess is that it will come down to who is willing to pay them the most. I don't think pretty scenery or proximity to nightclubs and other celebrities will enter into it. I don't see any Hughes ever leaving a nickel on the table (I'm not suggesting they should) but whoever they play for will almost certainly pay top dollar for it even if they play together.