Rust, paint, and fumes, oh my! Unfortunately we can't confirm, but this has 'Florida Man' written all over it.
This is what happens when idiocracy meets innovation. I grew up making hotdogs over a bonfire with roasting sticks, it can't be any worse than that. I'd let this sucker burn out a bit first. Lord only knows how much lacquer, Rust-oleum, paint, WD-40, and other chemicals are clinging to this filing cabinet.
As one commenter stated, "Won't last long, but I bet it works great!" Wise words. You'd be crazy to turn down a 4-tier grill! Summer only comes but once a year, so break out the smoker and break out the beer. Cheers.