Cowan, in camp with the All Blacks ahead of Saturday's Tri-Nations test against South Africa in Wellington, had already collected his wager off Canterbury's McCaw, while first five-eighth Colin Slade had yet to cough up the same amount and Cory Jane also lost a side bet with the Gore-born 29-year-old.
Cowan, who started Friday's test 60-14 test win against Fiji, said McCaw was less than pleased to stump up with the cash after Southland first five-eighth James Wilson kicked a late drop goal to claim a 22-19 win at Rugby Park in Christchurch.
"He didn't like handing that over at the airport," he revealed today.
"It was very pleasing to see Southland get a win after two disappointing losses - it was amazing to see that. It was very good coming down to breakfast this morning reading the Sunday papers with a big picture of Whopper (Southland captain Jamie Mackintosh) on the back holding the shield," he said.
Southland lifted the shield for the first time in 50 years in October 2009 beating yesterday's opponents 9-3 to send the deep south into raptures and they successfully defended it five times last season, including three nail-biting wins over national provincial opposition, before the red and blacks recaptured the Log 'o Wood.
Cowan, who played an integral role in their shield run, hoped the win would go some way to getting the union back to where it needed to be after some tough financial times.
"It's very hard as a player to go through that in the media when you're getting as a union especially when the likes of Jamie and myself have grown up there as local boys and it was a tough time for both of us. It is just pleasing to see them get a result like that last night after a lot of hard work from where they've been over the last six to 12 months.
"It's a start point, so hopefully they can kick on and hopefully get some credit back down there."
He said everyone was finding it tough going in Southland, including the supporters, but was optimistic the shield win would give the region a much-needed shot in the arm.
"As players we're doing our best to pull the crowds in and try and get some of the money back in. Hopefully we'll see a great crowd there next week when they host Counties."
