Go Tour: Sinnoh players who are raiding the two Origin Formes have been hit with an unfortunate revelation: The version that you picked leading up to the event determines if you can get a Signature Move of the Cover Legendary of the opposite ticket. This means that Diamond players are getting Origin Forme Dialga with Roar of Time, while Pearl players are getting Origin Forme Palkia with Spacial Rend. And while many players have expressed disappointment over this fact, those who have raided enough were able to quickly discover that this limitation isn't absolute.
Reddit user u/rwaterbender has taken to The Silph Road and compiled data from users, and has disovered what is very likely to be at least very close to the realistic odds of getting a Signature Move from an Origin Forme Palkia/Dialga when not playing the corresponding version.
Considering the fact that Roar of Time and Spacial Rend can't currently be obtained via TM/Elite TM, knowing the odds of getting the move for the dragon who's version can definitely help. But, regardless, save all of your Origin Formes with their Signature Moves, as they can be used for trades later!
Best of luck to everyone out there trying to get both of these powerful Pokemon with their Signature Moves and good IVs!