Given that their entire code base is written in C++, and switching to a different language would be a significant retooling for the team, I think it's reasonable to assume that it did not. Language choice is rarely made on the grounds of specific features, and is often made on the grounds of ergonomics and team knowledge.
A more revealing question is, "How are you dealing with memory safety in this implementation?" There are ways to improve memory safety in C++ through tooling and idiomatic style. Are these things being used?
A more revealing question is, "How are you dealing with memory safety in this implementation?" There are ways to improve memory safety in C++ through tooling and idiomatic style. Are these things being used?