Is This Even Possible?

so, my characters are buying ice-cream and the ice-cream employee turns into a fire daemon that wants to kill them

that's the context

is it possible for someone to put ice-cream in one o' those automatic tennis-ball-launcher-things and launch it without the machine dying?
_{because if not my MCs are doomed…}

I've never used one so I don't know if it would actually work
surely someone out there does know the inner workings of such machines…

I don't really know the answer to your question, but I do think this might be one of those cases where physics and logic don't matter as much.
If I read that in a story, I'd be amused, not picking it apart. And if you can have fire demons, I'm sure you can ignore a little bit of normal physics for the sake of the story.
That said, I'm guessing that unless the ice cream was frozen solid (and maybe even then) that the mechanisms in the machine would make a ball of ice cream fall apart and thus the machine couldn't launch it. But I'm also not very familiar with tennis ball launchers (although I'm slightly more familiar with baseball launchers).