yes. leave at 6:37am Crawford Dr. & Harper Rd., arrive 9:39am TWH. So appt. would have to be 10am.
Leave 6am bus at Crawford Dr. 
… arrive 9:12am at Union Station… 
… bus/streetcar to TWH.
if take taxi/uber from union station, might be able to make a 9:30am appt. not sure of taxi/uber avail at that time of the morning?
2.5 hours to get to Union Station is really awful. And a (further!) deterioration from the last time I made that trip in the Spring.
For next time, perhaps consider driving to Oshawa GO as the transit starting point.