For some reason matchmaking is missing from Spartan Ops (a feature native to the experience). It is also listed under the multiplayer tab, so clearly it was intended. When will matchmaking for the playlists be added? There is no point for the playlists at all without matchmaking, the same goes for Spartan Ops entirely.
If it makes you feel any better, I am wondering the same thing. Sorry I couldn’t provide you with anything more than that. I really would like Spartan Ops as a searchable matchmaking feature. Also custom games would be cool to somehow get into a matchmaking rotation.