My simplification was just that. And I agree that it would be better for these companies to include fork lengths in their charts.
But on the other hand, the Ultimate is in many ways closer to an endurance road bike in terms of geometry than new gravel bikes (like their own Ultimate G2). If they were spec'ing that bike with a 415mm monstercross fork, that would be weird in itself. A shorter 383mm fork actually makes sense in some ways, although that would mean that the bike would not support the advertised 45mm of tire clearance (and if they went with an MCX fork they would be in the 50s).
And yes, I found conflicts with other bikes on their site, and the differences aren't always consistent from bike to bike.