He absolutely is going easy for a Reason.  Flynn has testified in several ongoing cases.  The document says he has given substantial cooperation in the Russia probe and a separate criminal investigation that Mueller is running.     A memo filed in federal court for the District of Columbia on Tuesday confirmed that President Trump’s former top national security adviser, Michael Flynn, has been cooperating extensively with special counsel Robert Mueller’s investigation into Russian interference in the 2016 election. The document also revealed that Mueller is working on a separate criminal investigation, but it did not divulge any details about the focus of that probe. ...The documents filed on Tuesday also provide some hints of where Mueller’s Russia probe is focusing. It said Flynn had “provided firsthand information about the content and context of interactions” between Trump’s presidential transition team “and Russian government officials.” As an example, Mueller cited information Flynn provided prosecutors about his own contacts with Russia. Much of this portion of the document was heavily redacted, however.