The Chilean rider scored his second Welcome win at Tryon International Equestrian Center over Michel Vaillancourt's formidable course.
The pair were competing in just their second show together and first trip to Tryon in the Developing Jumper Six-Year-Old series.
Conor Swail continued his winning streak with a win aboard Vital Chance de la Roque to establish a commanding North American league lead.
The five-time Olympian moved into the number one spot for the first time in his career, ousting Daniel Deusser of Germany.
Sixty entries tackled Guilherme Jorge's course, with Parot and his relatively new partner topping the field.
A pair of 4-year-old mares – Ribery (60,000 euros) and Toulouse van het Beeckhof Z (32,000 euros) – have been sold to Canadian interests.
Harrie Smolders clinched victory with his anchorman ride aboard Monaco, while Team Ireland finished a very close second.
"I try to protect him now and just really aim for the classes that matter," said Tiffany of the 15-year-old gelding winning the final grand prix of the season at Tbird.
France finished second with 10 faults, Norway was third with 21 and the Swiss slotted into fourth with an uncharacteristic 25.
The Canadian rider steps up from a win in the U25 last week to record her first senior FEI victory in the $36,900 CSI2* 1.45m class.