Doctor going for trv to give an Exam. Help!

Hey everyone
Im PA from Pakistan trying to apply for trv while my spousal sponsorship is in process. I basically need to come to Canada to give a Canadian in person medical exam(nac osce ) that i have booked and has cost me 3000 dollars. At the time i thought i would get spousal pr but that still hasn’t happened and with the exam in September i am going through the trv route.

My only issue is that my wife being a Canadian citizen is in Pakistan and will be reaching Canada on Aug 1 but i need to apply for trv before she leaves bcz otherwise it may be too late for the exam … even if the trv was to come in.

The options that they are giving for reasons of wanting trv don’t have any exam ones only one that is most relevant to me is to visit wife … and ofc will be with my wife when im there but right now she isn’t and i am applying on that basis of visiting her. Even though i have also clearly said in my purpose letter and itinerary that my main purpose if trv is to give exam.