This photograph shows Dr Miller in the bottom left corner. The other men are all members of the Church Missionary Society in Zaria Province. Dr Walter Miller went on to write his memoirs where he actually remembers Captain Orr very fondly:
"But Emir Aliyu was not all bad, or he would not have won the regard and even affection of some of the best Resi- dents. Captain Orr, R.A., an Indian Frontier officer, and one of the best Residents ever appointed to Zaria Province, often told me that there were great qualities and latent powers for good in him. Mr. E. B. Laing, Resident of Zaria and a good judge of men, knew Aliyu well and thought highly of him. Orr, who after- wards became Governor of the Bahama Islands, deeply regretted the frequent furloughs necessary for adminis- trative officers in Nigeria, whereby it became impossible for one man to exert a continuous influence for good. He believed that with five consecutive years, as in India, a Resident could patiently do much, through friendship, conference, and gentle pressure in the right direction, to effect very wonderful results in character, statesman- ship, and mutual trust between ruler and people."
It is on page 128 of his REFLECTIONS OF A PIONEER. There is an article on Dr Miller's many years of missionary work in Nigeria here
Charles Orr's Memoirs Volume 5 | Charles Orr's Memoirs Volume 5b
