The Temple Of Time is confirmed - its seen in concept art of this image (Bottom Right)
As for the Vahi, they asked a question and the staff at the panel stated it was half of the mask, exact words can be found in their coverage. This occurred after the panel, as such BZP likely didn't hear it considering they didn't think of asking the question themselves.
As a rule of thumb its best to just ignore BZP's pessimistic nature as they dismissed Bionicle's return for the longest time despite the leaked images. They tend to ignore factual evidence for the sake of trying to tarnish the reputation of TTV.