What is the test for granting use immunity to a witness?

"The government is under no general obligation to grant use immunity to witnesses the defense designates as potentially helpful to its cause but who will invoke the Fifth Amendment if not immunized." United States v. Ebbers , 458 F.3d 110, 118 (2d Cir. 2006). Nevertheless, "under extraordinary circumstances, due process may require that the government confer use immunity on a witness for the defendant." United States v. Praetorius , 622 F.2d 1054, 1064 (2d Cir. 1979). A defendant requesting such relief must make a two-pronged showing:

Ebbers , 458 F.3d at 119 (internal quotation marks and citations omitted). "We review the courts factual findings about government actions and motive for clear error, but its ultimate balancing for abuse of discretion," although the situations in which conferring immunity would be required are "[s]o few and exceptional" that "we have yet to reverse a failure to immunize." United States v. Ferguson , 676 F.3d 260, 291 (2d Cir. 2011). This case is no exception.