There are a couple of separate issues as I see it.
First, they owe you what you earned and what they agreed to. Of that there is no doubt. You can file a complaint with the Employment Standards Branch and then they will get what you are owed in terms of what you earned. This will be simple and there will not be any charge for you in terms of fees.
The other issue is whether they owe you termination pay as you were clearly dismissed without just cause. In most cases when you work for an employer for less than three months you would not be entitled to termination pay but your case sounds a bit different than the usually case. The reason why is they knew you had a job but convinced you to take theirs instead by offering you more than you were getting at your then current job.
Then they not only breached their agreement with you but dismissed you for asserting your legal rights.
So in my view you may be able to sue them for damages even though you just started working there.
I suggest that you consult with an employment lawyer as your best next step with a view to retaining the lawyer to send them a demand letter and threatening damages.
If they are saying you are being dismissed for just cause and this may impact on your eligibility to get EI you will be able to explain to EI that you were dismissed when you demanded to be paid for overtime and can show them the proof of your complaint with the Consumer Protection Branch.
Does that help as a starting point?
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