Just as an illustration, and with no personal hard evidence that the Lampyridae was at Overberg, it is important to realise that there was ongoing co-operation between South africa and NATO/Western countries during the Apartheid era, and the sanctions era.
I'm going to just mention a few projects and let the forum members decide for themselves. All the below mentioned examples are from the sanctions era in South Africa.
Look at the 6X6 vehicle entry that was eventually won by the indigineous 8X8 Rooikat.
I wonder which engine powered the TTD Main Battle Tank project.
What type of diesel engines were manufactured by Atlantis Diesel Engines (ADE) for the military and civil sectors?
What design was the submarine blueprints purchased by South Africa in the 1980's?
Which country built the submarines that were unnaffordable to Argentina, and were thus offered to South Africa for a very brief period of time for completion?
A clue: There is a German link in all the above.
Some non German questions below.
Also, which model Snecma ATAR 9K-50 powered the Mirage F1, and which model powered the Cheetah?
What electronics and main gun armament equipped the South African Navy strike craft?
What nationality was Carvers chief designer? (Although freedom of labour must be taken into account here. Ex colleagues do chat though!)
etc... etc. These above examples are just off the top of my head, without any dipping into my library at home.
Things are always not the way they seem......
I for one would not discount Lampy from being in South Africa just on account of sanctions. Overberg is also a magnificentally equipped, top-of-the-range test range, in a relatively geopgraphically isolated position, with a low area population density, benefitting from a very long downrange distance. This was the exact reasons for it's establishment there.
I can provide some answers to anyone who doesn't know the answers to the above questions.
Once again, I don't know if it happened but Lampy sure fitted the timeline above.