Not only is he waving the green in that corner when the Bianchi collision happened, he stopped at 1:13 when it was happening, looked down at the situation, then continued to wave the green flag until around 2:30 when someone climbed up the stairs and spoke to him.
Considering the original crash, heavy equipment and track workers inside the barriers, and another very violent collision right at the foot of this flag stand, I can only imagine that corner worker and anyone advising him on the radios is in some trouble.