That was, I believe, they judge they wanted to get in front of. At one point there was another judge in that district that they didn't want to get in front of and a law firm just so happened to employ the second judge's son (? IIRC).
Judge Jacqueline Scott Corley didn't recuse herself from hearing the Microsoft-Activision FTC case just because her son works at Microsoft (and ruled in msfts favor!)
So are recusals for such conflicts really optional?