Can you confirm which files are missing for you?
If you are referring to the RTSDK-BinaryPack\Cpp-C\Eta folder, this contains libraries (prebuilt from non-open source code) as targets for the rest of the RTSDK to use as linkable target objects.
There is no equivalent Ema folder.
Any required EMA libraries can be found in the \Cpp-C\Ema\Libs folder
You can also refer to the Cpp-C\Ema\Docs\RTSDK_C_Installation_Guide.pdf document for further details.
If you are new to Realtime SDK, I recommend you refer to the QuickStart pages - in particular, the ESDK Build System page (apologies for the naming confusion - we are currently undergoing a rebranding process).