He fixed the issue on the first attempt by applying the patch mentioned in the linked thread.
This was caused by the linker (fixable problem inside of Unreal Build Tool).
The 2nd issue he got is entirely different thing though.
Error C1001 Internal compiler error.
indicates that compiler (MSVC) has crashed.
Not sure if it was related to inability to open the files (see other errors)
but this is generally something that is impossible to fix on our end, unless you get a different compiler version (newer one) or find and change the code that is causing the crash.
You better off creating a new forum thread at this point. This was probably a very specific crash.