I really have a hard time understanding why people feel the need to mix their lizards and dogs.
I hear people constantly showing off pics of their lizard with dogs, or telling stories of how their dogs come up and check out their lizards, how their lizard and dog get along, blah blah blah.... no.
Theres no reason, ABSOLUTELY NO REASON, for you to mix monitors and dogs, reptiles of any species and dogs really.
A perfect example is what happened here. On the other hand, you sound like a total dumbass.
To paraphrase abit:
"Oh hey, Ive managed to let more than one of my animals get killed by my dog"... means, hi, im a dumbass.
"Yeah, so, Im not going to outright admit it, but I abused my animal to the point of shooting it with a pellet gun" .... means, im a really messed up person.
"You think Ill get brought up on cruelty charges?"
Do I think you will? I hope so.
Should you? Most definitely.
Why would you even have your dog out and about the house while you have your lizard out? Thats the great thing about a dog- YOU CAN PUT THEM OUTSIDE!
Hell, crate the hateful lil beast until you're done dealing with your other animals. This isnt rocket science man.
If you dont have the common sense to remove your dog (by which I mean straight lock his ass up, put him outside, lock him in another room) when handling your reptiles, then you REALLY need to think about re-homing your lizards, and prolly your dog too.
Its not like this is a child that can open doors or anything- how could you let 3 of your iguanas be killed by the same dog?
These arent toys that you can just go "Oops, dog broke it! Time to get a new one!"- these are living things, and your lack of respect for their lives paints a very poor picture of you as a person.
Take some serious responsibility, or get out of the hobby man... a monitor dying due to poor husbandry is one thing, a monitor; ANY ANIMAL, being killed by another because of owner incompetence like this is pathetic.