1) It is using the Legion frame as a base. Every logo after BC takes the base frame and makes small adjustments to it beyond color. This one is copying Legion's. You can see this if you look near the Lordaeron L's in the outer frame, above and to the left of the "W" in Warcraft. The curly bit there is directly copied from the Legion logo--except that this curl is Legion specific, not part of the base frame.
This was one of the tweaks Legion did to the frame to get that cleaner Legion architecture aesthetic.
Base form:
The top spikes are also using Legion's frame instead of the base.
Base form:
This is highly suggestive of someone altering an existing logo rather than a new one from Blizzard, which should be working off the base and modifying, not working off the Legion and doing so.
The chain at the bottom (while a nice touch) is also suspect. It's very simple compared to the rest of the logo and to every logo even used and the center below the C should have a bunch of diagonal spikes, a feature of every single logo. And the side spikes also appear to be directly taken from the legion version.
The logo is also extremely flat for something that looks as though it's meant to be animated, it's missing the copyright symbol which should be just to the right of the T, parallel with its top, the blue highlights on the "Warcraft" look like they were sloppily painted or paint-bucketed on (you can even see where the highlight goes out past the C in one place
The lightsource itself here seems confusd, it's only applying to the bottom of the letters, and doing so evenly when it appears to be lit from the center bottom, and so should be much weaker towards the left and right side of "Warcraft", and the text seems poorly color-balanced for the palette. They adjust the yellow to better fit the colors being used, the globe is a bit too bright, saturated and attention drawing.
And if you look carefully above the W you can see there is a mismatch in the frame where it should be continuous.
Not saying it's impossible it's real, but lots of little mistakes and "off" things. Wow logos are professionally done. Highly likely to be fake.