Training partners Mathew Ellerton and Simon Zahra are being investigated over a positive swab.
Epic Saga has tested positive to clenbuterol after winning the Tatura Cup on April 4.
Clenbuterol is a bronchodilator and is a prohibited substance.
Melbourne Cup-winning trainer Brian Jenkins had two horses scratched from Pakenham on Thursday after they received raceday treatment.
Deputy chairman of stewards Robert Cram said stewards acted on a report from Racing Victoria's compliance assurance team that Crown Halo and Seguro had Vicks VapoRub applied to them.
Vicks VapoRub contains the active ingredients camphor and menthol, which act as a decongestant, and are prohibited substances under the rules of racing.
Cram said the inquiry had been adjourned.
Jenkins trained Jezabeel to win the 1998 Melbourne Cup.