IANAL so I don't know anything about anything. But I think the subtext of this story is one of the little guy getting comically screwed by a bigger player. If the South West Terminal, with capacity for 52000 tonnes of grain, wants to swing their dick on a farmer over 86 tonnes of undelivered grain, they'll find a way to win. Regardless of the law, going after a guy over a thumbs up emoji is audacious, at least.
I expect that in the future, someone in the farmer's position with bigger stakes and more money to play with will bring on a herd of lawyers to throw down a thousand esoteric & byzantine arguments & get a win. Maybe that's unfounded pessimism, I don't know. You just don't seem to hear stories about rich people taking Ls like this.