Code gets reviewed for production at 6am by a guy freshly rousted out of bed who committed some of it four hours earlier, and who is doing this at the insistence of a "frantic" colleague, the fix involves "a bunch of commits" from more than one person, and his main worry is that he might be held responsible for a hidden back door maliciously inserted by his coworker? That's like driving home drunk with your headlights off and worrying that your car could get blown up by a drone because of eroding limits on the use of military force against civilians. I realize it's hypothetical, but man, fix your glaring problems first before you worry about unlikely scenarios.