I think Dwight is being used by Negan. He doles out real intel and also misleading intel to each minion. He's testing Dwight as well as using him to pass on incorrect or in this case, incomplete information. I doubt that Dwight intentionally misled Rick and Daryl to set them up. Negan just has a lot more smarts than his appearance and persona lets on. I don't think Simon has the same intel as the rest. They are all given specific information in order for Negan to weed out the traitor(s). He's crazy and amoral but he's not stupid.
I think Gregory will be killed by someone, possibly Daryl before Dwight will. Dwight is playing with fire here. He is seeding both masters with distrust. He will likely pay heavily for that one way or another.
I could be wrong but I think Dwight sincerely wants to go back to a place where he can have a wife, a somewhat normal life and some freedoms which are costly but better than Sanctuary existence.
Honestly, I'm shocked at the extent of Dwight's knowledge of all the bases. I'm also shocked that Jesus knows where everything is, exits included in Saviordom. How does he know all this shit?
Time will tell.