Copy 19th century Wills from Hong Kong Probate Registry

My great-great grandfather, Andrew Johnston, died in 1896 in California, but lived and worked in Hong Kong.  Probate was granted for him in Hong Kong and I'd love to see a copy of his Will.  I've emailed Hong Kong Probate Registry who have replied saying that an application for a deceased's Will "can be made by or with the consent of the grantee of the probate".  As that person is long gone, I wondered if this was the end of the road, or has anyone managed to obtain a copy of a 19th century Will from Hong Kong Probate Registry?  Many thanks.