I think it bears mention that despite Zodiark essentially being a glorified mecha that requires a heart/pilot to act, the souls that went into him were still conscious as we see them directly cry out to us and beg us to save him/them from Fandaniel (and the destruction he sought) and we even see them walk around on the moons surface.

Now their presence might be due to the towers binding him being shattered but we do speak with Hythlodaeus.

There is a implication that they were stuck immobile and aware for 12 000 years and could do nothing but cast their gaze at the ruined shard that once was their home.
Their hope of salvation edging a little bit closer each time a rejoining was performed only to be betrayed by a member of the convocation for the second time (counting Venat)

A terrible end for a tragic figure.