Yeah they are. Despite all the things they have other people doing, there’s a ton of stuff which they don’t have outsourced. And the contributions from others will (likely) only be filling a portion of what you see.

Ironically, the coding which you refer to is probably the area they’re doing the least work in, as the infrastructure of the game is already in place from Episode 1. Sure they might be adding new types of attacks/mini-games which may require more coding, but the conversation editor, use of consumables, attacks, etc. are all coded already — all they have to do is update the database with new values.