What a scam. Do you have the reason for the tow in writing?
If so, and none of what has been mentioned works, take them to small claims court. You will be out $100 instead of $268 but they will get nothing. You can always try adding in other things like however much you had to pay Lyft/Uber to get to the tow yard. Make the judge decide.
https://www.alberta.ca/court-fees