If you hold the Canadian issue they will not allow you to convert to OTC?
Champignon has been cease traded for a couple of months in CA, but trades nicely here. Your broker may simply want nothing to do with it. I would call and talk to a couple of reps. Or you could open a free brokerage account with someone else more flexible.
Chains, indoor dining ETF pleasure, dining out Foodservice delivery Supplies and small wares Restaurant centric companies i.e. Maitre D Website "Open Table" Bar service