Is it permissible for the questioner to fast with the UAE, given that it differs by one day from Oman, where he resides, and will his Eid be with the UAE if there is a difference in the day of Eid?

You are correct in your fasting, fasting with the people of the Emirates, and your fast is valid. If the sighting of Shawwal is confirmed there, then break your fast with them, for the distance between the two countries is close, and there is no difference in their moonrises. This is the more preponderant opinion. If you fear being misunderstood for breaking the fast or for fasting, then do so secretly.