With three rounds to go just five points separate Colombia in second place and Ecuador in eighth. The top four qualify automatically for World Cup while the fifth placed team will almost certainly face the All Whites in a home and away series.
Vickery said other than Brazil, who have already secured top spot and a place in Russia, the rest of the South American teams have looked less than impressive.
"You have to go back 20 years to remember a crop of South American teams that are as weak as the current ones, Brazil excepted," he told Martin Devlin on Radio Sport's Devlin Radio Show.
"They're all a much of a muchness, we don't know next who will cross the finish line and qualify automatically for Russia or who's going to come fifth and meet the representatives from Oceania. It's all very very tight and I think we won't have things decided until the last ball is kicked in the final round next month."
Lionel Messi's Argentina currently sit in fifth place with three remaining games against Venezuela, Peru and Ecuador. They failed to beat all three teams in the earlier rounds.
Argentina have struggled to score goals, netting just 15 in 15 games the campaign so far which is two less than bottom placed Venezuela who the face off against tomorrow in Buenos Aires.
Vickery says Colombia are the best of the rest and expects Argentina to qualify but says the other South American teams are going backwards.
"They are onto their third coach of what has been a very disappointing campaign for them. They are really struggling for a blend and they have serious problems in some areas of the pitch especially in defence. But you look at the attacking talent available to them and you can't help but thinking sooner or later they will be able to find a blend and get the most out of this astonishing array of attacking talent," he said.
The first leg will be played in Wellington in November before a second leg in South America a week later.
Vickery said the All Whites' style could make things difficult for certain South American nations.
"If you get Peru or Ecuador in a playoff that long throw into the opposing penalty box that could really cause some damage."
Vickery said Ecuador would be the worst team to face because of the altitude at their home ground, which sits 800 metres above sea level and said there will be hostile atmospheres wherever New Zealand go.
He added Peru is the team New Zealand would probably most want to finish in fifth place as they haven't qualified for a World Cup since 1982 and have shown potential to buckle under pressure.