Welcome to Smogon! Take a moment to read the Introduction to Smogon for a run-down on everything Smogon, and make sure you take some time to read the global rules.
Though on a serious note, this pretty much confirms that Goomy is in the Dragon egg-group, but do you suppose it could be in others? Amorphous seems like a likely candidate. Any good things it could get from that?
Er, actually I'm not too familiar with breeding myself, but I always thought it worked that certain moves can be passed down by the father onto a child of a different species. I suppose it's possible I did something wrong, but it's not likely.
Well, I'll look into it and see if there's any place where I might have made a mistake, or if there's been a change in mechanics. But it looks like Goodra does not get Dragon Dance at the moment. I hope I can prove that wrong...