I'm at the beginning of "Dark Chambers of our Minds" and have the optional goal of telling Tharael about the dream. I'm sure I did this the first time I played through, and that I found him in the shed, because I remember him explaining it was implanted by psionics last time I was at the temple. But Tharael is nowhere to be found, not in the shed or temple or anywhere else.
I'm going to continue without the extra little bit of exp from this, but I'm reporting it anyway just in case it's a bug. Attached are a pair of saves, one from just before going to sleep and one when I'm looking for Tharael. In between I did parts of "Our Mark on this World", if that makes a difference.