From some friends I know in MLB front offices I have been told the Brewers are not in on Crochet, but take this with a grain of salt they could be wrong. They have checked in on him but that is as far as the discussions went. From what I have been told the price on Crochet has actually gone up since the trade deadline. The White Sox want more than what they were asking for during the deadline earlier this year and it looks like they may just get what they want as there are three desperate teams wanting to add pitching without adding to their payroll majorly in the Red Sox, Yankees and Phillies with the Mets being interested if Burnes doesn't sign with them.
Black doesn't really have a position in MLB and he is more of a DH. The DH position in MLB front offices has been devalued a lot. So take Black's value and cut it in basically half. This is why the White Sox wouldn't want Black regardless if he is a top 100 prospect. It is not filling holes in their MLB roster it is filling holes in their prospect list. The White Sox are devoid of talent at the MLB level but not at the minor league level at least pitching wise. They have two really good pitching prospects that they are probably looking to build around and Black just doesn't fill that void in terms of a positional player.
Wilken had a horrible year after getting hit in the face. He continued that in the AFL which was the Brewers trying to get him more comfortable at the plate. The getting hit in the face has made him a bit more timid at the plate causing him to be late in recognizing pitches out of the pitchers hand. The Brewers wanted him to get more comfortable at the plate and seeing the ball better. I am not sure if it worked or not. Other teams have this same viewpoint on Wilken now. I doubt Wilken even makes the top 150 prospects from what I have heard from some scouts they don't see him as an everyday MLB player since the injury occurred. His on base ability has taken the biggest hit since the injury occurred and you could see some signs of this before the injury.