Then that "procedure" is incorrect. Whether or not the result would be different if the tester had been in the vehicle is debatable. The machine dictates both the test procedure and the RESULT.
Of cause he failed them, the roller brake tester told him the brakes were not up to the required efficiency. You admit you have done no further work on them so why expect them to pass on retest.
This is never ending, in his opinion the lights were faulty, he failed, end of story
FFS why???? Do you think the elves at the bottom of your garden have been doing a bit of DIY in the middle of the night.