How much Rust was used for The Finals, an upcoming game by Embark?

Can someone from Embark let us know how much Rust was used for The Finals? Is the game engine written in Rust?

https://www.reachthefinals.com/

Teaser: https://www.youtube.com/watch?v=Gq-R9GjW-Ik

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For context, Embark Studios is a big supporter of Rust community.