I've now talked on the phone with Mr. Triplett about this. The OUS does not check on how he actually spends the money. He says that these amounts are simply paid to Chancellor Persteiner on a monthly basis as "salary supplements" or additional compensation, added to his $280,900 base. Which brings it up to $342,940.
In addition he gets a car, and is also reimbursed about $20,000 a year for in and out of state travel expenses. Then of course there's the $50,000 a year or so for Treetops. And the $7,000 or so he charges OUS students for his personal food.