If 63 terminated in Niagara Falls, NY, it is likely passengers were totally on their own to travel 2 miles to Niagara Falls, ON to catch a bus, any bus, and deal with CBSA issues. Most US passengers do not know squat about GO Transit.
As with Amtrak 's total cop out last week with the West Side line outage with no customer service people at Croton Harmon to guide people, no information as to which MN train to catch at GCT, bewildered passengers at GCT were in fact calling Uber, taking wild goose chases on Metro North to New Haven, no holding of train 64 at Albany for a terminated 68, which is normally the last train south, no operation into GCT For 3 days - I would not attempt travel any longer on the Empire Corridor without buying Trip Insurance.