Doesn't say, might be a paralogue but I lean more towards a GHB.
Nevermind. Generic units across all GHB maps have the same stats. In the video we can see a Bow Fighter with 37 HP, while GHB Bow Fighters have 38 HP (Hard difficulty). The only other Bow Fighter with 37 HP can be found in Chapter 10-4 (Hard), therefor I believe that what we are seeing is Chapter 13-4 (Hard) (with a chance of it being Chapter 13-5).