Since posting this, I've learned that the Backpack the Camel has production code 705 but was aired as the 8th episode.
See: https://en.wikipedia.org/wiki/List_of_Wild_Kratts_episodes#Season_7_(2023%E2%80%9326)
(Why TheMovieDB lists it as episode number 7 is still a bit of a mystery, though.)

For ...

What is the ultimate upstream source of the episode numbers? I anticipate that you'll say XMLTV, but the ultimate issue is that the episode numbers that the HDHR gives to some of its recording files don't match what other metadata providers/systems use and that's causing confusion.

Here are two ...