It's not canon. The actor isn't the writer of the show for that matter.
However, I seriously wonder if it will remain as a non-canon thing knowing that the show does try to appeal to the fandom and that there are many in this fandom who would love to see RD fly the gay flag. That, and of course, though Faust was the one who created the show, from my understanding, she isn't really all that much in control of it these days...
It really doesn't in my opinion either...
Personally, I don't think I'll be staying long if they do make her, (or any of the other more pivotal characters) a homosexual.