So you want to get to the MK as early as possible? If DH goes the 'adventurous route', it will take him much longer:
He'll have to drive to the MK parking lot, park the car and wait for a tram back to the TTC from the MK parking lot. The monorail operates about one hour prior to park opening so if that's running, he'll then have to go to the platform and wait for it then take it to the MK which is 3 stops away or he could walk over to the Poly and catch it from there where it's 2 stops away.
His scenario is going to take a lot more time than just taking the Blue Flag over to the CR and walking to the MK. The walk from the CR dock to the MK is about 10 - 15 minutes. Let us know what DH decides to do