I received an e-mail from a very helpful lady who kindly supplied the following information. I would be very pleased to expand on this if anyone has further information.
On a recent visit to South Africa, I photographed some Mingay
gravestones in a churchyard at Bulwer, Kwazulu-Natal. I believe there are still
Mingays living in the area.
Hope these will help someone make connections. Bulwer is a small
place in a beautiful region of Kwazulu-Natal, near Ixopo. The church was built
in the 1880s from hand-sawn yellowwood, hence its nickname. Unfortunately, it
was closed when we were there so we didn't see the inside, but there is a photo