I don't think Portland is interested in Monroe. They seem to like the low maintenance, defensive center to get along with their ball dominant, shot happy perimeter guys. Plumlee gives them great playmaking and everything else they need from the center position. Ezeli is a great backup when healthy. Why try to fit in a low post scorer, who isn't great at running the floor and isn't the best rim protector? Lillard and McCollum aren't particularly good defenders. You need guys to cover their mistakes.
From the teams you mentioned the Pelicans make the most sense. Given AD's footspeed a frontcourt of him and Monroe looks pretty scary on paper. And if Ad goes down they have someone to keep the offense afloat down low. But this means, that the Pelicans don't opt for playing AD at center and trying to play a smallish, running style with Hill/Gee/Cunningham/Jones at PF. With all those combo forwards on the roster and with the best players outside of AD at the guard positions, I expect a lot of 3 guard lineups with AD at center. Still Monroe is a huge upgrade over any of their pretty crappy big guys. But if Gentry likes to run (
), than he will be in a backup role, meaning the Pelicans will only offer very little value for him.
The Monroe situation is kinda sad. Such a rock solid player, but most teams simply go in a completely different direction and have no need for him.