On the other hand, I'm not sure why a leaker would take the time to show something this, I dunno, pedestrian. A dwarf, a harpy, a rock dino, and zones that don't look unique in any particular way. The place isn't supposed to be Outland or Shadowlands level of weird but at least fake some landmark or whatever.
Occam's razor to me says they're a bit more likely to be real than not due to the effort involved in making it vs the effort involved in leaking it.
The webpage leaks however don't help its case. Again if you can get the webpage why not just reveal the name of the xpack and not just the places that are Avaloren and Khaz Algar, the two names we happen to actually know?