[Hahaha him giving out info before he's asked for it, that's a good one.]

That's all we do know, currently.

From what I understand, they all had a dream that told them to enter the temple and that a pathway would be opened. The only reason we were also warned was due to Takeba's own involvement.

Regardless, since the expedition no one has been able to open the door again. Information about what happened is limited to the video which you all saw.