When Freddy returns to the doorway he came through? It’ll open, just not to the Sanctum of the Wizard. He’ll be looking in to one of the Metro-Library’s large archival rooms. He’s got the gift of Solomon on his side, so he’s going to know immediately that this means one of two things.
(A) Either his access to the Sanctum has been Revoked. This would require either the Wizard or someone with -MORE- power than the Wizard to have essentially assumed possession of the Sanctum in his absence.
(B) Someone else opened one of the myriad of other doors from the outside, that lead to the Sanctum. Another doorway has either been left opened or is being held open. Solomon might give Freddy information on how ‘Gateways’ work (taken from the pages of the DC Adventure Journal). Essentially they form wormholes between two points. They can span time or space, or both if the person who created it was powerful enough. However when the wormhole is connected, it can’t connect to elsewhere. (Does Freddy watch Stargate?)
Unfortunately, I can’t really give you a clue as to which of those options it is yet. The same stuff that triggered Freddy’s meeting with Black Adam, also triggered another little Mini-SM, that is still pending. Soon as I’m done there will be more information to be had.
That’s the bad news.
The good news is that Freddy can absolutely recognize Teth-Adahm. After walking a mile in his boots, thanks to Solomon, he knows Teth’s mortal coil almost as well as he knows his own.