I basically don't know anything about how Gatekeeper runs or how they keep the balance sheet positive, so all I have is rank speculation and a tiny bit of data
Gatekeeper is in the not necessarily enviable spot where they have chase card coverage for MPO elite series events. They produce produce some non DGPT A tier coverage. If you look at their views on YouTube they top out at around 35K for chase card, with more typical views being in the 15K range, and lots of other content that has more like 1K views. They have a Patreon that has 110 patrons and produces ~$550 per month and get an unknown amount of revenue from sponsored (non YouTube) ads. At least by the picture on their website, they have a production crew that consists of as many as 5 people. They have something coming from merchandise sales, but likely no too much. This doesn't look like an overwhelmingly robust financial picture.
Compare this to Jomez that has ~3200 patrons that produce at least somewhere between $15K and $60K each month in subscription revenue each month, and whose youtube card coverage videos get somewhere between upwards of 200K views, and whose other content usually gets ~100K views. Their content also seems to generates robust merchandise sales. Assuredly they are spending a lot more for broadcast rights now than the zero they were paying in the past, but they are actually generating the kind of money that allows them to sign a contract for $500K in rights over two years.
GKPro also has a Patreaon that generates ~$550 per month, but they have a direct subscription through their website for both Skins and FPO coverage. YouTube videos look like they are mostly in the 20K to 30K range for cards and 40K to 60K for skins. In addition, I'm assuming they are paid by DGPT to produce the silver series content.
One has to wonder how much Gatekeeper can pay their commentators and why they have Dustin Mouret at all. He has a recent PDGA number, playing his first tournament in 2021. It wouldn't surprise me if they're is some personal connection between Gatekeeper and Dustin. That our he has become a big fan of disc golf or sees opportunity of growth in the field. Why else is he willing to follow doing commentary on these videos? It is not likely for the small amount of money.
At least one reddit comment indicates that he is also doing this from offsite. Especially when he was doing solo commentating earlier in the year, I can see this actually simplifying the process of getting commentary done. No need to get non tech savvy DGers mic'ed up in "studio". This could also be the reason for some issues with having a broadcast partner. If they aren't in the same location, coordinating commentary doesn't work as smoothly.
As for Earhart, he is simply no longer available, as he is signed up to do work with DGN.