Seems the implication is that some sort of race tampering has happened at this meeting.

Horses are in the race, usually to win, regardless of what price The Market decides they should start at.
If a number of winners start way over the Odds, then you must look for some sort of link between them.
If there ain't one, then its just one of them things.

Losing money as a Punter ain't fun, and its easy to blame someone else when we get it wrong, especially a number of times in a row.