n.b.

It was time to leave, and the HR lady came to me and said I would have to sign a release letter and send it back within 2 work days (the following Monday was a holiday), otherwise I would not get any of the remaining pay

I'm not familiar with the law in Canada, but I rather suspect that it's similar to America, so a bit of advice for the young and impressionable: virtually no threat to not pay an employee wages is worth taking seriously. Don't sign anything. Say you'll run it by your lawyer. You don't even need to have a lawyer when you say that, but the prospect of your lawyer going to the employment commission and saying "My client was denied wages. Do you need me to say anything else or can we just proceed directly to 'He gets them'?" will generally make them back off.

I mean, as one point among many, your lawyer is going to say "You think he was a consultant? We have written representations from you that he was a FTE, and you treated him as a FTE, for example in attempting to control his working hours. It is materially against his interests to be a consultant, because this implies that you haven't been paying employment taxes on him. That's unfortunate, but it's not our problem, and rather than stick him with the bill for $X,000 in back taxes we're just going to tell the tax authorities that he's been maliciously reclassified and that you're delinquent in your obligations. Given that this will likely trigger an audit and potentially hundreds of thousands of dollars of fines for you, how about we just agree to give my client what he has coming to him, and you report an inadvertent paperwork screwup to the tax authority when you pay your fair share?"

I have absolutely no reason to ever use this but I'm absolutely going to throw money at the author because I'm a sucker for pixel art and this looks incredible. (I spent like five minutes staring at the zombie .gif, slackjawed.)