Please note that Betfair removed the original market for the 15:30 Cheltenham race and subsequently replaced with a different (reformed) market.
If the races were loaded prior to the removal (and before the reformed market was offered) then TBE would have no knowledge of the new market and no betting would have taken place.
If the races were loaded after the formation of the replacement market, then TBE will have processed the market as per normal.
Note - Betfair does not indicate that a market has been replaced via the API, so it is not possible to know when this occurs. Fortunately, it happens very rarely.