I wonder If RRL Grindrod would indirectly benefit...
Not sure, I don't see a causal link (as a layman) between the Transnet contracts and Grindrod.
"The contracts were awarded to CSR Zhuzhou Electric Locomotive and Bombardier Transportation SA to supply 599 electric locomotives, while General Electric South Africa Technologies and CNR Rolling Stock South Africa (Pty) Ltd would build and supply 465 diesel locomotives."
[Source]
AND YET
"Grindrod has ventured into rail infrastructure investment in Africa. It owns 51% of RRL Grindrod Locomotives. Its locomotives "were consistently priced better than other original equipment manufacturers" [Source]
The reason Grindrod didn't get the contracts (and DIRECTLY benefit) is possibly just that they don't have that capacity yet.
"supply 465 diesel locomotives" compared to Grindrod's current capacity:
"The capacity of the RRL Grindrod Locomotives plant had increased to 100 locomotives a year, up from just 25 in 2012"
Awesome company, also have it in my long-term portfolio