I don't see why not, there is a drop off area there.
The only problem will be that it will take a while for your DH to get back to the TTC to meet up with you. There is no way to get into the parking lot from there without going all the way back toward the toll plaza and there is a left turn that will get him into the MK parking lot without having to go thru the toll plaza again.
Approx a 2 mile drive back to the parking lot and then take the tram to TTC figure about 15-20 minutes to get back to you.