That looks very likely. On ScotlandsPeople it's indexed as: NEILL, WILLIAM ALEXAND, (mother's m/n:) REAOCH M 1883 644 / 12 / 35 GORBALS
South Africa, Cape Province, Probate Records of the Master of the High Court, 1834-1989; https://familysearch.org/ark:/61903/3:1:3Q9M-C91S-39HS-8?cc=2517051&wc=WV44-9LY%3A1598042322
I found this, I know they were in SA. He was a springbok rugby union player