(The Grand High Priestess will at some point interrupt their negotiations, within the Rope Trick, to say that the portal is up, and she's heading back to Kelesh.)

(The Grand High Priestess will at some point interrupt their negotiations, within the Rope Trick, to say that the portal is up; they need to take down that Rope Trick and put up another one right by the portal, so Tira can cast a Forbiddance covering the demiplane except the portal.  After which Tira can finally head back to Kelesh.)