it is understandable it really is about separation and is discrimination by skin color. On the other side is, if a white troupe decided to have a whites only audience for a portion of its performance run it would create outrage and harsh condemnation from the black community.
If you’re going to preach equality you cannot on the other hand rule for a discriminating policy even if for one performance.
Personally, if a company of any type, acting troupe or other informed me there is to be a day set aside for black only or white only participation, they would lose my participation altogether even if it was said to be for a good cause. No cause is righteous when it calls for separation.