The advice of a third-party consultant can be extremely valuable. They bring a different perspective that can cause a refreshing change in an organization. That expertise in a niche market may allow members of the organization to try new things and innovate in a variety of ways.
Or it may not.
Bringing in consultants can also have the opposite effect. If you do not allow your employees the responsibility to fail then they will never attain the level of engagement needed to become successful.
Empower people first. Give them a difficult task and let them fail. It is only at that time that a well-thought-out choice of a third party consultant can come in and provide valuable, constructive criticism, and feedback - acting as a catalyst toward a better result.