I would TM your Dragonite to Outrage. If you don't power up any other dragon types, the Dragonites will be by far your best counters to Palkia raids when gen 4 comes. OR vs DM does make a relevant difference, OR is a better move AND 2-bar which makes it much nicer to use and less risky.
DM is a community day exclusive, but it's worse than the normal moveset and you have the shiny with it anyway for collection purposes, so I don't think you're losing out on much. In the end, it depends on how you feel about it.