The rather laboriously titled "Wrexham and Denbighshire Advertiser and Cheshire Shropshire and North Wales Register" carried a short article on his death (17-03-1900). It noted that he was 6' 3" tall, "proportionately "big", he looked a veritable giant". Perhaps unwisely Walter had previously written home saying the Boers couldn't shoot.
In June 1897 Walter, as a Welshman, he was from Wrecsam, had been chosen as one of four troopers of the 2nd Life Guards to represent each country of the United Kingdom to head Queen Victoria's Diamond Jubilee Procession.
The officer is Cpt OH Ames, 2nd Life Guards, at 6'8" he was the tallest officer in the Army. I have no idea who the other three troopers are, they don't appear to be listed in the Jubilee Medal rolls - perhaps they did not receive the Jubilee medal?
Cpt Ames did not serve in the war. The Household Cavalry (1st & 2nd Life Guards and Royal Horse Guards) only sent a composite squadron. Again Walter was hand picked for service.
The YouTube film is https://www.youtube.com/watch?v=HxohzRe9D6w