He held his nerve well in the final round with an even-par 72 to finish inside the top 32 by three strokes.
Masterton professional Ben Campbell, who was playing at the same venue as Fox, and Mount Maunganui pro Josh Geary were not as fortunate.
Campbell had rounds of 73, 75, 73 and 75 for an eight-over par total to finish in 62nd place in Texas.
Meanwhile Geary, who was looking to return to the Web.com Tour, had a frustrating week at The Standard Club in Georgia.
The 29-year-old had rounds of 72, 73, 72 and 71 to finish in a share of 49th place at even-par, five shots back from the top 31 players who advanced to the next stage.
The four-time winner on the Charles Tour will now turn his attention to a busy schedule on the PGA Tour of Australasia which includes his title defence at the Western Australian Open.
On the OneAsia Tour, Wellington professional Nick Gillespie has earned his biggest pay day of $54,000 after a solid week at the Nanshan China Masters.
The former Fiji Open Champion had rounds of 68, 68, 74 and 73 for a one-under par total at the Nanshan International Golf Club to finish in fifth place.
The one-time winner on the Charles Tour was eight shots back from the local hero Li Hao-Tong who lived up to his favourite billing with a four-stroke win.
Fellow Wellington professional Gareth Paddison, a perennial contender on the OneAsia Tour, will be disappointed with his final round four-over par 76 that saw him slip to a share of 11th place.
Perth-based Kiwi Michael Long was tied 28th, Brad Shilton was tied 50th, and Auckland professional Richard Lee saved his worst for last when he signed for a 10-over par 82 to finish tied 66th.
Meanwhile, Danny Lee and Tim Wilkinson have produced unspectacular final rounds at the season-opening Frys.com Open in California on the PGA Tour.
Lee carded a one-over 73 today as he drifted to a share of 46th at three-under for the week, while Wilkinson signed for the same score as he jumped to a tie for 65th at two-over.
Korean Sang-moon Bae won the tournament by two shots after a final-round 73 saw him finish at 15-under.