I'm still making my way through the rulebook but
1) Could I play this through discord? Or do we have to be in the same room?
2) There's no GM for this game, right?
It's designed for a GM - the role that the rules refer to as "Control".
The combat rules are maybe a little bit crunchy, as written, to run entirely without a map grid - but if you handwave the weapon range rules, there's no reason you can't run it as pure theatre of the mind. (I certainly don't see a problem running it unmodified in something like Roll20.)