Also yes, the leftmost number in the Finch diagram should definitely be a 3
Since he says this, it seems that he did mean to have a ④ in the diagram.
On hex-prism boards the Finch and Cohen can also move one step at right angles to the hex plane like a regular Wazir, likewise the BADBABA (Curved Dabbarider) 2 steps, ERTBUCHET 3, and BOCBLER 4.
Since he says this, it seems that he did mean to have a ④ in the diagram.