Got a good source on the Knaak story, and I'll share now that it's official. Clemson came in with around $600k in NIL after he had already agreed to an under-slot deal with the Brewers on draft day (not sure of the exact money), and to keep the timeline short, this is where we wound up in the end.
The Brewers and even other organizations are not thrilled with Clemson here, as this is not really something colleges do for returning college players. Once they've gone and agreed with a pro team, they don't come in with a late offer. Until that agreement is in place, it's different. Once they have a verbal agreement, colleges back off and look elsewhere so as not to hurt relations with pro organizations.
As has been mentioned, this may start a new trend, and in a few years maybe this will be much more normal, but for right now it's definitely not.
FWIW, there are some whispers that Knaak's dad was pretty involved in all of this, though I don't have nearly as good a source on that, but probably smart to keep in mind that while he did back out of an agreement, we are talking about a 21-year-old here who was potentially being pulled in a lot of directions by his parents, agent, college coaches, etc.