The Herald understands that Madgwick left the country the following month under his new name, before a warrant was issued for his arrest in August 2012.
"The warrant was issued due to Mr Madgwick failing to appear on a number of fraud-related charges," said a police spokesman, who confirmed the warrant was still active.
The revelations follow the case of convicted murderer and child abuser Phillip John Smith, who fled to Brazil while on temporary release from Springhill prison using a passport he obtained under his birth name.
A story that ran in the Herald on Sunday in October 2010 showed that Madgwick was alleged to have spent more than $100,000 using credit card accounts belonging to up to 10 other people - who included family members, sparking an overhaul of Westpac's online application process.
Police began investigating him after the Westpac credit card fraud investigation department laid a complaint. Westpac investigators stated Madgwick used the details of others to get credit cards and applied for them online. He was listed on credit card application forms as an "additional cardholder" and under bank rules at the time, any spending was charged to the primary card holder.
Among those who were stung by Madgwick's alleged con was a man he met at an Auckland bar.
The man, who became friends with Madgwick and drank regularly with him, said he was "astounded" when a collection agency called and demanded $22,000 for debt on a Westpac credit card. The man, who asked to remain anonymous, said Madgwick spent the money during a two-month splurge in 2009. He bought groceries from food chain Nosh, liquor at bars and at wholesalers and made many cash advances. The man recognised Madgwick when he saw his picture on a news bulletin on Boxing Day.
The Ministry of Foreign Affairs and Trade said Madgwick's family were receiving consular assistance. It's understood that Madgwick was to appear before a court in Phuket but he had not yet sought any help from ministry officials.
