Horner Jr said: "It got pretty emotional over the line because Lee and Amy (McDonald, the trainer) work pretty hard and I know Lee loves this horse.
"It's one of his favourites but he obviously couldn't ride him, so it's rewarding that it could be me.
"He fell off at Terang and broke his ankle in two places.
Darryl Horner Jnr celebrating his win before the line
"Obviously, he did all he could to be back and realised he couldn't be, so I stepped in, rode he horse in a couple of trials and won on him at Hamilton and now here we are."
Horner Jr's fine was added to a punishment of £166 for excessive use of the whip, handed out after an earlier race.
Flying Agent (left) jumping a fence in the race
Punters were stunned that the stunt on Flying Agent cost the jockey a significant amount of cash.
One said: "$1000. Absolutely laughable. Can't have fun or enjoy any celebration. The fun police at it again."
While another added: "I've got $100 to help pay the fine. Anyone that knows him can you get him to get in touch."