2012 R2 does not support Win 10 LTSB 2016.
Running the MSI directly is not supported and the /a switch doesn't install MSIs anyway.
To locally install the client agent, you always need to run ccmsetup. From there you can check ccmsetup.log. As mentioned though, LTSB 2016 is not supported so it may or may not even work.
Jason | http://blog.configmgrftw.com | @jasonsandys