The bigger issue here is that ML set the expectation, he did not throw his HC under the bus, he stood up for him and supported him, exactly what he should have done.
What DA did was the complete opposite by throwing his team under the bus and stand united with his players. Dennis Allen chose not to support his team, that was clearly his decision. Whether Mickey sees that as a problem or not I have no idea. But I can guarantee you any effective leadership starts with choosing what is best for your team and supporting them, not dividing them.