Not all EX bus devices show up in device explorer (as proved by the fact that if you plug in an older Jeti RX, without having updated the firmware, you often can't see it). The Cortex PRO video doesn't mention anything about Jeti device explorer.
I have no idea whether the Cortex will be visible in device explorer or not but before everyone gets over-excited, until we all get some more details, I wouldn't necessarily assume that it will just because it works with EX Bus.