Any credible evidence that they get enough money from the sponsorships to be considered fully funded by them? Or that ground news uses influence over these channels?

I can throw a dart and hit a random podcast that has been sponsored by blue chew for years, but that doesn't mean said podcast is funded by them or bends to their whims.

IMO your comment is pure conspiracy theory.

Why would thet be a conspiracy theory. The public facing guy who is behind Warfronts has 4 other channels that peddle content unrelated to natsec/warfare. If you follow "cappy army" and the drama he went through at "task and purpose" his former employer it becomes pretty clear that there are entire media companies behind what looks like "a single hobbyist content creator expat living in Prague" ...