The Lua VM is a C API, so yes, you should be able to use it from Rust easily.
11 Interacting with foreign code
One of Rust's aims, as a system programming language, is to interoperate well with C code.
Can you re-phrase the question? I don't understand what you're asking.
My question is how much logistic and scripting support should I get if I write a game engine in rust....
That's been the trend so far, with C++ being the popular systems programming language. It will be a long time until managed languages replace C++ for this job.
Can anyone probably guess if a systems programming language will be used in future to write game engines, and not managed application languages?