Hold on, some new info I just reminded myself about just scanning the Sermons. Vivec builds his own realm called the Provisional House at the centre of the Secret Door. So possibly that is the House of Boethiah? It would make sense that ALMSIVI would claim the souls of their worshipers rather than let them go straight to the Daedra. So it might just essentially be a Tribunal Soul Cairn.
It's likely that the Chimer would have went to the actual realm of Boethiah when they died.
As for why Boethiah, it's never stated but he's essentially the "first among equal" of the Good Daedra. He was the first to contact the Chimer and teach them about the Psijic Endeavor and "how to build Houses". He was also the Anticipation of Ayem who was the oldest, most loved and most powerful of the Tribunal.
Hold on, some new info I just reminded myself about just scanning the Sermons. Vivec builds his own realm called the Provisional House at the centre of the Secret Door. So possibly that is the House of Boethiah? It would make sense that ALMSIVI would claim the souls of their worshipers rather than let them go straight to the Daedra. So it might just essentially be a Tribunal Soul Cairn.
It's likely that the Chimer would have went to the actual realm of Boethiah when they died.
As for why Boethiah, it's never stated but he's essentially the "first among equal" of the Good Daedra. He was the first to contact the Chimer and teach them about the Psijic Endeavor and "how to build Houses". He was also the Anticipation of Ayem who was the oldest, most loved and most powerful of the Tribunal.