The god of dreams gained access to the first angel of telepathy's memories, so he learned that Legion was suspected of being a killer and that this killer was in the spiritual dimension.
No one in the Mind Hunter organization knew Legion's identity. This information about the killer in the spiritual dimension was the only link that the god of dreams had, and it wouldn't cost anything to confirm, so the god of dreams went to the spiritual dimension.
The god of dreams took the Mindscape to reach his destination. Since he already had the memories of the destination from the first angel's mind, he was able to reach this destination very quickly.
When he reached the destination, he saw the horde of blood beasts trying to get into a sealed fortress. None of the blood beasts sensed him because he used the Sensory Hijack divine ability to make them unable to perceive him.
Unfortunately, he too couldn't get into the fortress. Despite his great power, the fortress was impenetrable to him.
