Here is the expanded screen for the race in question. Horse #3 has a slightly higher PL probability/odds value of 15.51 (rounded to 15.5) or odds of
5.4-1 compared to Horse #1 which has probability of 15.43 or odds of
5.5-1. That is why RDSS ranked the #3 as rank 2 and the #1 as rank 3, which I agree is different by 1 rank position from what is showing on the TS ProfitLine screen where BOTH are shown with ProfitLine odds of 6-1 (i.e. rounded UP) and the ranks are reversed for some reason. All these numbers come from the
same TS ProfitLine screen (just under the surface). That's the technical answer for where RDSS gets its ranks.
Which numbers would you rather have?
Here is the TwinSpires ProfitLine page shown above with slightly different ranks.
Ted