Isn't the blackstaff black? The staff in the picture is brown.
Aside from artistic license, it could be how the picture is lit by the burning Chicago city making the wood appear lighter...but I do admit, I am speculating wildly.
Again: artistic license. It could explain any discrepancies.
But yeah, it doesn't physically match.
The Blackstaff is shorter, thicker, less shaped & polished. It's a walking-stick / cane height.
I think this is Harry's new staff, either Eb finally got him a blank, or he used wood from the island.
And yeah... seems to have mounted the Knife / Spear.
I don't remember it saying it was cane height...just because it might be Mother Winter's walking stick (possibly, but unconfirmed) doesn't make it necessarily the size an old crone would use for a walking cane/stick. And many supernatural creatures can be the height they wish to, so it has no bearing. Hell, the fact that it's a "walking stick" merely is a representation of part of her power - and seems to limit her ability to travel. What it actually IS, is anyone's guess. But my money is it is somewhat similar to a mantle, part of winter in physical form, severed from her - like Sauron and the One Ring.
But it probably is more likely a new staff made from the island. Still, it would be cool for Harry to get the Blackstaff (sooner than later - although perhaps the fact he
hasn't got it yet signifies how much that will change the game i.e. he will have MUCH bigger problems)
I bloody hope it is the end of the masquerade, otherwise Jim has to keep it in sync with our world - which is both difficult and depressing enough. A divergence would be nice. It would be exciting for it all to come undone and vindicating for Harry to be right, which of course means that he will be blamed.