When you went up to Baguio, the engine temp can rise and it should because you're forcing the engine to work more. As long as it goes back to its original normal reading, you should be fine. Otherwise, there's something wrong. Do you recall what the Corolla's temp reading was prior to the trip to Baguio? When you had the radiator overhauled, do you know if they removed the thermostat? It's a common misconception that removing the thermostat is better but if you search the archives here you'll find out that the thermostat is crucial in maintaining optimal engine temperature to provide you with the most efficient performance that is also flexible enough when encountering hill climbs like that or stop and go traffic.