If Damien had started creating like a normal person, he probably would've had a decent amount of time before people noticed his movements.
However, the change in Death's Hold was too big. The great tree was enough to attract attention from all corners of the island, and the fact that the forest itself became as large as a country even more.
Again, "change" wasn't a thing in this realm. The forest couldn't become anything it wasn't even if it had all the power in the world.
The only way to enact change in the Land of Nothingness was for an individual to actively do so.
Naturally, everyone was going to pay attention to the mysterious person who changed Death's Hold.
There were hundreds of "Noble Lords" on the second island. Most of them were reclusive and only focused on ways to find a way to the third island. They were the ones who bought land but did not use it.