I'm not a chemist either but as someone who as partaken and knows other people who have also partaken, the dosages you have to take in order for this to become an issue are way beyond what would seem reasonable for someone who's not heavily dependent and tolerant.

You would have to be taking grams and grams of the stuff on the regular; infrequent or one-off dosages won't cause bladder damage.

Edit: even in the article you can see that the guy developed "K bladder" after taking 15g per day. 15g is a truly scary amount of powder to be ingesting.