Think positive. Any idea how long your snake was breathing the nasty smoke? Also depends how thick it was. Risk increases as the
exposure increases, either longer time or higher concentration. But snakes pretty much only have one functional lung too, which is why
I really hate to see owners smoke around their snakes too.
When electronics malfunction like this, it's pretty much going to be melted-burning plastic that makes the fumes, since metal components
don't burn. Burning plastic is very toxic, but let's hope the exposure was minimal.
(This is a downside of cages with so little ventilation, to promote humidity.)