Apparently, the disturbance that will be created during their advancement to a god will be worse than the one they created when they advanced to the godling rank. The disturbance will be so loud that it will attract the attention of many divine beings.
So even though, just like the god of dreams, half of their advancement will not be in the physical dimension, they still chose somewhere where they would be able to avoid disturbance for the first half of the advancement.
Thanks to the Environmental Adaptation divine ability, staying in the spiritual dimension is not a problem for them. They can stay there as long as they need.
The spiritual storm that they will create during their advancement will blend in with the chaotic atmosphere of the spiritual dimension. That way, no seer will be able to easily find them through the traces of their advancement. This is very important to them after they have learned their lesson from when the god of dreams found them.
