would there be another avenue to report this activity?
Directors represent the stockholders and it is the stockholders who have the ultimate authority to purge their company of anything undesirable. Such an action would play out at a stockholder's meeting and would require the approval of a majority of the shares of the corporation--a heavy lift in all but the most closely held corporations. Other than a corporate action to unseat one or more properly elected director(s), it would seem that the only recourse would be for the new director to sue one or more other directors for damages (which would have to be enumerated)--also a heavy lift.
Unless they are stockholders or directors, the "some" who are saying there is discrimination of some kind, have no voice in the matter. If they feel strongly enough, they are always free to terminate their employment and look for employment in a banking company with a corporate culture more to their liking.