Just call us the bullet dodgers. The mites in Townsville were, as I had first thought, not capable of infecting A. mellifera. And with a closer read of the original research by Robert's team, I understand why. You don't even need to do a DNA analysis, because the data is actually staring you in the face.
When the V. jacobsonii mites jumped to mellifera in the PNG, they were unable to breed on A. cerana. They had undergone a speciation event, and changed their hosts completely. They are not opportunistic, but specific. Therefore, the mites in Townsville couldn't have been a danger, because they were breeding in an A. cerana hive. Granted, we don't want any more cerana on the continent, either, but that cat's been out of the bag for a while.
Postscript: An acquaintance pointed out that a possibly more realistic threat is that jacobsonii mites could act as a one-off vector for DWV, from cerana to mellifera. They wouldn't have to be be reproductively viable mites; they would only have to carry the virus and go from an infected cerana hive to an uninfected mellifera hive. That would be scary.
(appologies for the pokemon joke.... it's one of those things you either get, or you don't)