There's a flock of students and vaccinated Americans coming in this August. My friend had to wait for 2 hours in the plane and another 5 hours in line -- this was on August 7 when hotel quarantine was still in effect. Hopefully it will die down.
I've read a few cases of students in your situation and they were fine. If the immigration officer asks you for one, you can tell him/her that you didn't receive it in your GCkey account.
I think it's better if you submit the official one through webform, there's no harm in submitting a webform. An official statement from the university carries more weight and credibility.
You applied for a study permit and the LOI type showed Permit -WP / Permis - PT. This means that you will get both a study permit and a co op work permit.
Fully vaccinated travellers from all countries will be allowed to travel to Canada for non essential reasons starting on September 7. Here's hoping that non essential TRVs will be processed soon.
Completed means IRCC has received your biometrics. BVL is usually issued together with the decision although that doesn't always seem to be the case now.