I have a male horse that just tested really well in the CK, so of course there is a problem with him in his maiden race.
The jockey said basically "We lost this race before it started. The horse sweated up badly."
I assume one of the the pacifiers will help with this.
Any ideas? I am surprised on how nothing can be found on any of these pacifiers in way of their usage.

I guess I will try blinkers first, to keep him from seeing the other horses beside him in the gate house.

Sweating up badly is a roll of the dice event in game. Horses with excitable dispositions have it happen more and laid back horses less. But it can happen in any race. It won't effect an export.

Your head lad will tell you when you need a pacifier. If he does, look up the parents and see if they wore them. They almost always do. Use the pacifier type they used. Using them when they aren't recommended usually results in an unsettled horse who runs poorly.