Where does the exhaust currently go from gas powered clothes dryers? Please excuse me if this seems a dumb question, but I don't even know anyone with a clothes dryer in Australia
If the exhaust goes anywhere outside, it should be safe to put it thru the greenhouse imo. It's not like you'll spend long spells breathing it yourself, and I can't see why it would harm the plants?
PP, who's just guessing that plants wouldn't be poisoned by CO, but would probably be able to split off the carbon just like they do with CO2.... but I don't know.