Some of what you said could be possible (the use of Eden for example, that could have accelerated the Light abundance).

But it's clearly stated that Ardbert killing Loghrif is what triggered the Flood of Light by breaking the equilibrium between Light and Darkness drastically.
If everything would have happened like Emet and Loghrif wanted, it wouldn't have happened Eden or not.

So, for now, I will stay on that Ardbert and his companions are those who triggered the Flood, it's there choice to not do what was planned by killing Elidibus servant and to track and kill Loghrif, and not the choice of anyone else.

And if at the end we learn that Ardbert & co aren't responsible for the Flood, it wouldn't like it, their story would lost meanings.