The problem with greyhound racing compared to the other two codes is you are guilty regardless of the level in the dog.
This is my understanding from our own case a few years ago. Science doesnt matter because whether or not you, a staff member or someone in public is responsible for the positive, the onus is on the trainer.
What I am surprised about is the new standard the stewards spouted about setting in the case i was involved in were thrown out of the window for this one. This is very dissapointing to say the least.
As a side note, all staff and handlers of the dog shoukd have been requested aswell. Not just one member. There is no consistency at all on these investigations and fines