Why does the hand and dial differ so much...? Hmm...
You could get a geiger counter to see if it has radium I suppose.
I'm not an expert but I think the caseback is more a concern, I searched up the number and there is at least one more watch that has the same numbers as yours. Unless you bought the exact same one? But this one has a different dial.
I just googled "Y17746 10681945" and there was a WUS thread about it. https://forums.watchuseek.com/f20/omega-military-watch-help-please-778976-2.html
Too many red flags.. consider getting a refund?
I guess it's an acceptable deal for 200, but it just doesn't sit right with me still....so someone removed the dial or something in the 6 or so years this has first surfaced, and even changed the hands. I would feel like I'm wearing a corpse of sorts.
Also I was shocked to learn before that the dirty dozen watches were not used actually during WWII. It was a letdown, but, I still want to get a good one someday as well.
But of course, if it makes you happy wearing it, it all doesn't matter- wear in good health!
Omega WWW watch of the dirty dozen was delivered at a time where the war was over in Europe but was still going on in the Pacific region - so it is only partly true that it was not used during war time