"Once we do that, we can wrap up the inquiry.''
Stewards want to question inconsistencies in the statements made by Johns and Robinson and the phone records obtained by Racing NSW regarding who spoke to who and when.
More Joyous, the second favourite in the race won by All Too Hard, finished second last prompting a routine stewards' inquiry into her poor performance.
The inquiry escalated when stewards became aware of Singleton's public sacking of Waterhouse via post-race television interviews amid allegations her son had inside knowledge the mare could not win because she was, in Johns' words, ``off''.
The investigation revealed More Joyous had been treated for heat in her neck in the lead-up to the race but was subsequently passed fit to run by the stable vet and Singleton's vet.
Stewards were concerned Gai Waterhouse had not reported the treatment so the Racing NSW vet could also examine the horse.
They also examined all betting records on the race and found nothing untoward.
Singleton added further fuel to the fire last week when he called on Johns to ``man up'' and front the inquiry.
"If I found out that Andrew Johns, who I have a high regard for as has the whole Australian sporting community, has rung up and told me a lot of nonsense and has done damage not only to Gai and myself but to Tom and Robbie (Waterhouse), I'll apologise to anyone who was hurt by it,'' Singleton told the Seven Network.
"He owes me an apology. He needs to front up and man up.
"If he embellished it he owes me an apology and I owe them (the Waterhouses) an apology.''
Any apology might be rejected after Singleton took aim at Gai Waterhouse in a column published by Fairfax Media on Sunday where he lambasted the trainer for her comments to him last week in the inquiry that he was a ``sham'' and that he had been drunk on raceday.
Singleton admitted the relationship had been soured by Waterhouse's selection of barrier 11 for More Joyous in last year's Cox Plate against his wishes, something he put down to the trainer's ``sleep deprivation''.
More Joyous finished 11th of 14 in the Cox Plate. Her most recent win was in September last year and Singleton has yet to decide whether she will race on under another trainer.
-AAP