Answer
The route should be changed because the pilot would lose continuous visual awareness of the aircraft and its relationship to people, aircraft, and obstacles. The pilot should not rely on the expectation that it will reappear safely.
Explanation
VLOS is not the same as knowing approximately where the aircraft should be. When trees block the view, the pilot loses the real time safety picture needed to avoid conflicts. The safe plan keeps the aircraft observable or uses an approval designed for a different kind of operation.