According to the Guinness World Record 1984 on the page 34 (Japanese edition), there were officially two highest IQ persons holding 197 with SD15.75 (σ6.1587) on Stanford -Binet Oxford Analysis New-Zealand version.
The one of them was the ISPE founder, Christopher Philip Harding.
http://esoteriqsociety.com/esoterists/christopher-philip-harding/
Another one was Wolfgang Lenzen who was born on west German in 1962, lived in Cape Town of South Africa and was a member of the Mega society.
Someone who know how to contact to him, please let the ESOTERIQ founder, Masaaki Yamauchi.