reg ( snipped-for-privacy@somewhere.fsten.co.uk) gurgled happily, sounding much like they were saying :
And if you'd bothered to read, you'd understand that in taking the car away, the tester MUST do a complete test, not a partial retest, when the car is next presented, and is entitled to charge full fee to do so.
He's perfectly entitled to say "No, sorry, I'm too busy to do a test. If you leave it with me for the work, then I'll try and fit it in for the test, too."
By working on the car after taking it away, the OP also removed any possibility of appealing to VOSA.