I can't find a Charles George Frederick Wheeler on the medal roll for HHS Shah.
The article you posted states:
"In 1879 he fought with a naval brigade in the Zulu War against Cetewayo, and took part in the battle of Ulundi."
The only member of the naval brigade I am aware of having served at Ulundi was Lt. A. B. Milne, Naval ADC to Lord Chelmsford.
Petty Officer Tom