Amateurs! That's why you have a bag of holding... Fold body, insert into bag, dump in some marsh. If you want to be safe, pore some holy water over the body... If no BoH is available, just fold the body in some chests, use either a donkey or Tensor's Floating Disk to move the chests. Or if you're afraid of witnesses, set up a scene where they killed each other... Be creative!
When you murderize someone, even if they're 'evil' or attacked/tried to kidnap you, in a town or city, you better clean up after yourself! Prestidigitation cleaning is your friend! Unless you have some kind of Paladin running the town or law enforcement (never a good idea!), folks are willing to look the other way, unless you press their faces into the act.
That said, the main DM sounds like an ^&$#, a bit of a power hungry king mentality. If 22 people depend on you, you better be available. If you're not, make sure the other DMs know how to replace you, if not don't take the 'realistic' approach unless it was made
very clear beforehand what would happen if you did xyz (especially when you see something like that happening eventually a mile away). Your main job as a DM is to make it fun for everyone, that some of the group didn't subscribe to your sense of propriety, isn't a good reason to punish them.
If you have the 'title' of main DM, you're also responsible for what your underling DM does. This is how an hierarchy works, naughty word rolls down, but responsibility is supposed to roll up.
Sidenote: I've been playing a Neutral Warlock (Great Old One) that's been very upset with cultists and rebels trying to wyrmnap their blue dragon wyrmling friend, another group of Vecna cultists having murdered their human friend. Let's just say that the bag of holding has been handy and have become proficient at Tetris stacking bodies behind secret doors...
