From a previous post i stated that he knew the basics. Which is all that is needed to listen to instructions during the M1 Exit test. He plans on taking the RTI safety court. So it shouldn't be a problem.
So your father knows the basics of the English language? So when the instructors explain what push/counter steering, feathering the clutch, looking where you want to go, etc., he'll understand completely and fully? Those words and phrases aren't basic English.
If he can't even pass his M1 test without needing a translator, what makes you think he'll be able to pass the safety course?