Geertruida Bastiaans du Toit - MH match - Need help deciding validity

I have just added Geertruida Bastiaans du Toit as the daughter of Guillaume du Toit &Sara Cochet, using the My Heritage matches.

One of our great SA researchers, Private, noticed within minutes and pointed out to me that as far as we know those two only had one daughter - Helena http://www.ballfamilyrecords.co.uk/gous/I209.html. Now neither my previous research - already on the profile - nor internet searches right now (including the First Fifty Years Project) show up Geertruida or her supposed brother: Guillaum du Toit (according to MH Matches) , so I'm inclined to just delete them both.

I have, however, been working on Geni for about 12 hrs non-stop, updating (some really exciting stuff - including pushing our tree back a couple of generations in more than one place!) so it might be that I'm missing something important due to being a bit cross-eyed.
Thoughts anyone, especially about if she & her brother might fit in somewhere else?