I will guess those tutorials were included by Debraj to capture the basic formation/implementation of walk cycles that can be created in OpenToonz (and almost any animation software).
Edit: I may also just as likely inadvertently grabbed them thinking they were Toonz tutorials in my attempt to collect and put a spotlight on Debraj's various tutorials.
To my knowledge there is no relationship between the Toon Boom Harmony and Open Toonz (or Toonz/Toonz Harlequin) software.
If they have ever exchanged code that has not been publicly acknowledged.
The similarity in names does sometimes produce confusion.
I would imagine the similarity is intentional on the part of business decisions that might find profit in potential users mistaking one for the other.