The NYT article relies mostly on named sources, not anonymous sources. So it doesn't seem to be intentionally leaked information. And the board looks horrible,

The NYT article relies mostly on named sources, not anonymous sources. So it doesn't seem to be intentionally leaked information. And the board looks horrible, slow to act, behind the curve, reacting to external pressure instead of leading. So it would not be in the board's interest to do a "coordinated PR push" and fire Muilenburg after the stories were published.