i do trust the mechanic as i have used him for years but i will still keep a close eye on things ie. coolant levels and temp gauge, leaks ect. I feel that if he thought it was needed he would have done a rad test ect.
We had the car on the lift looking at things for almost an hour. originally quoted 40 to test the rad or half hour labour no tax off the books but lady said dont worry about it. i still gave her 40 CAD for the hour of lift time and overall inspection because i like them and they are honest lol

 

Follow the troubleshooting steps in the FSM

https://www.nicoclub.com/service-man...F2010%2FCO.pdf

 

Drive it when it is dry out. If you see steam you have a radiator issue or a hose is damaged/loose.

 

Honest perhaps?
Qualified, I don't think so!
Forget what he thought!

When you finally get around to doing a proper pressure test you'll have your answer.