I've found good info on DMD medal site where one of his medal's is for sale. (see below) it ends by saying he was mentioned in Lord Roberts' Dispatch - London Gazette 10 September 1901) I've ben unable to find this and would appreciate any help offered. I've only found him on passage home. Thank you in advance.
Queen's South Africa Medal, bars, 'Cape Colony','Wittebergen', officially engraved naming - Lt. Colonel. R.BROOKE, Imperial Yeomanry. (REGINALD BROOKE - Born 17 September 1854: Granted a Commission, Sub. Lieutenant 102nd.Foot from 5 June 1875: Transferred to 1st.Life Guards 10 February 1877: Lieutenant 5 June 1878: Resigned 11 October 1882: With the outbreak of the South African War he obtained a Commission as Lieutenant & Quartermaster 11th.Battalion,Imperial Yeomanry: Shown as proceeded to South Africa from 28 February 1900, (Officer in Charge of Details, Cape Town): Lieutenant 13 November 1900: Captain (Unattached List) from 1 January 1901: Invalided to England 10 May 1901: Resigned 18 August 1901: Commissioned Lieutenant-Colonel of the newly formed 39th.Battalion,Imperial Yeomanry from 28 February 1902: Returned from South Africa, 22 October 1902 and retired the following day: Mentioned in Lord Roberts' Dispatch - London Gazette 10 September 1901)