It was the second career title for Lynn and his first since taking the KLM Open nine years ago.
He finished at 18-under-par 266, one shot better than Justin Walters, who registered a final-round 5-under 66 at Oceanico Victoria Golf Club.
Overnight leader Paul Waring stumbled to an even-par 71, ending in a three-way tie for third place at 16-under with Stephen Gallacher (66) and Bernd Wiesberger (67).
Sharing sixth place one shot further back were Henne Otto (70) and Jamie Donaldson.
Celebrity Families of 2014 [PHOTOS]