Ok, so why did he go running off into the Bright? Slavers indicates that the Soul Gem was stolen after the events of C2. (4) Duke Justinian romps off to the Bright after the events of C2, where he is wounded.
This is not necessary, but it's my interpretation. The party didn't have to travel overland for the return trip, as they had a magic item to help with that, but the text on C2 page 5 says they were escorted to the tower on the way out, seemingly indicating an overland route. (3) You have to allow for enough time for the party of adventurers to get from the Duchy to Inverness. My guess is that the revolt happened at the end of 570, which would place the meeting that is described on page 4 of C2 sometime ca Readying 571. This is especially true in a nation like the Duchy, which is not particularly known for it's religiosity. I imagine the construction of a temple takes some time, and although it doesn't need to be finished in order for the revolt to happen, the amount of unrest needed to cause mass rioting does take time to build. As the revolt was in response to the high temple taxes and the raizing of the Temple of Zilchus, one would assume these events took time to occur. (2) It had to happen three months after the Temple Coalition Revolt (C2, pg 4). The reason Hodar was in prison, was for violating said edict. (1) It had to happen after the Duke's edict banning certain "sorceries which (he) had forbidden to all the peopleā of Urnst. There are a few clues as to when C2 took place: I don't have CORS3-03 Return to the Ghost Tower of Inverness, but I have recently run through C2 Ghost Tower of Inverness with a fine-toothed comb.