Plan cannot partially surrender collateral securing commercial mortgage while paying balance of bifurcated mortgage; alternatives in § 1325(a)(5) “for the treatment of secured claims of non-consenting secured creditors . . . are mutually exclusive.” Citing First Brandon National Bank v. Kerwin (In re Kerwin), 996 F.2d 552 (2d Cir. June 11, 1993) (Newman, Cardamone, Mahoney), § 1325(a)(5)(C) requires surrender of all property.