I don't know about the wind effect for the Arkansas Derby or a downhill stretch but that second fraction was really slow if the timer/chart was correct.

Magnum Moon on the front end after a 23.34 first quarter crawls 25.26 for the second.

In the past 19 Ark Derby's the slowest 2nd quarter for the race was 24.88 and that was by a 43-1 shot on the front end who stopped after a half and finished dead last.The fastest was 23.22.

Average second quarter was 23.88 for all nineteen races.
If you take out the fastest and slowest it averages out to 23.86

The next slowest second quarter after that 24.88 was 24.42

If the 25.26 was correct for Magnum Moon they should be able to finish fast.
They ran it like a grass race.