I'd probably be a little scared of Santa too
I think that if I subjected my pups to that, they'd give into their prey-drive and Santa would be missing an arm and candle....with that being said, my pups seem to eventually tune out distracting things...they will now nap or just sit quietly and watch the lawnmower guys go back and forth through our yard with all kinds of loud machines... but they still bark their heads off at a random leaf that blows across the back porch. I personally would not turn on the Santa if it seemed to overly stress out or agitate the dogs and they didn't calm down after a while. I hope that you and Maggie are able to come to some sort of compromise lol