Sharon and Jack Osbourne are adamant the Menendez brothers stay locked up, even with a looming resentencing that could set them free in mere days. Despite an abundance of calls for the brothers’ release, the mother-son duo can’t shake their disbelief that Erik and Lyle resorted to murdering their parents instead of “just leaving”, RadarOnline.com can reveal. The Menendez brother’s attorney, Mark Geragos, has persuaded the D.A. to rule in favor of a resentencing — potentially leading to their murder conviction being reduced to involuntary manslaughter. Erik, 53, and Lyle, 56, brutally shot thei…