Musgrave is a beast. Usually no problems when used with bumps, as the channel is practically limitless in supported values. But for visible colors it should output values in the 0-1 range. You can get away with multiply and add nodes, but that involves tedious amounts of trial and error to arrive at something useful.
So I made this node group, where I can see when the values clip with preview enabled, adjust until nothing clips, then turn off preview. Now I have a normalized value I can actually control.
Edit: I just noticed your top part look ok. If baking “diffuse”, check that direct and indirect is turned off in the bake settings, for an albedo map you only want the color info. Normal maps and lighting info excluded, I always use go via emit. I don’t remember if this tutorial is high to low baking, which I don’t really do.
I recommend activating node wrangler addon so you can easily preview the results from a node.