No.
Eryndor immediately rejected the second option. Both the real body descending and the idea of Co-founder Morris being someone else.
He had long guessed that eldritch entities couldn't leave Forbidden Domains due to the Forbidden Film. There should be similar constraints on the eldritch being in the abyss of this secret realm, else it would've already taken him.
There was no need to rely on Co-founder Morris to plot and push him into the abyss.
An eldritch entity somehow replacing Co-founder Morris? Granted, even if it was not a true body but some clone, it would be incredibly difficult to hide under the radar of the Human Federation.
The Human Federation wasn't THAT incompetent that they would fail to notice an imposter existing in their headquarters.
Eryndor had plenty of faith in Dr. Kirchoff, the man who led the Human Federation to its current height while protecting humanity from anomalies and the Eight Outer Domains.
