I imagine 45 minutes is plenty of time for an assistant and a heat sealer to make up the cookies.
I'm not sure about the tile thing. There are several ways to do this, depending on how close he got to the chosen tile or the others. Could be anything from a force to a "peek" (if not physical, than virtual)
That was how I assumed he did the cookie effect, I just can't imagine hiring an assistant to make cookies and fill them? It just seems so out of the ordinary. . .
I'm positive it wasn't a force, the only this he remotly said about the tiles is the 3 squiggles gets chosen alot. He turned around while it was chosen and the tile was held in between the mans hands or in his pocket so I can't see how he could have "peeked" as such the tile.