The analogy for parents/grandparents sponsorship is actually somewhat similar to your case: it’s currently done on a lottery basis, and will change to a first come first serve basis soon, but either way, someone could meet all the requirements and have made great contributions to Canada, or greater than many other applicants, yet still unable to sponsor his/her parents because failing to win the lottery or the delivery service was slightly slower than others, or the internet had a glitch and missed the chance to sign up before all the slots were taken ... that’s definitely not fair, but that’s how the rule works with IRCC