OK, so if it's "without cause" then it's a layoff. He's been given 2 weeks, which is the statutory minimum. The courts frequently order more pay in lieu of notice than the minimum of course, depending on the circumstances of the termination, the job market, how long the employee was there, etc..
He's been offered an additional $2500 as an incentive to sign a waiver, saying that he won't sue them for the dismissal. That's pretty common.
It's also common for the employer to give the employee a very tight deadline to sign the waiver, so that there's little time to consult with a lawyer.
His salary is about $1500 per week, so the offer is essentially another week and a half of pay in lieu of notice. If the money is in exchange for the waiver then it shouldn't be considered employment income, but it might be employment income. I can't tell which, and the only difference is whether it's considered taxable and if so then that's a further delay of a couple of weeks before he can get EI.
So let's call it 4 weeks pay in lieu of notice, after 2 1/2 years of employment. That's not the worst offer I've ever seen, but it's not great either. I'd consider that the minimum he could expect from a judge. Not that this has to go to court, but if he gets a lawyer to write a letter to the employer telling them to go pound salt and to offer more or else they all go to court, I'm sure that the employer would raise their offer.
As a further incentive to stay out of court, the employer has already paid the first two weeks of the severance, so going to court is going to be over how many further weeks. It might be 2 more, it might be 6 more. But with fewer dollars at stake, people are less likely to want to hire a lawyer over it.
So I think he's due more. But it's up to him. He should contact the employer and tell them that a deadline of Wednesday isn't going to work for him as he has to get legal advice, and that his lawyer will reply to them in short order. He needs to make an appointment very soon with a civil/employment lawyer. It's not a "labour law" question, that's the law concerning labour unions.
Or he can sign the form and take the money, especially if he can get another similar job in short order and also get a good reference letter from the employer.
Does that make sense? Please reply with question or comment. If I've answered you then I'd appreciate a positive service rating please.