The Stoke striker and his team-mates left Dublin en route to their qualifier against Sweden at the Friends Arena in Stockholm on Friday evening before Austria's visit to the Aviva Stadium next Tuesday.
In reality, all three sides are battling for second place in Group C behind current leaders and favourites Germany, with a play-off berth up for grabs.
The Swedes, who drew 4-4 in Berlin in October, currently lead the way with seven points, one more than Giovanni Trapattoni's men, with the Austrians a further two points adrift, and Walters knows what happens in the next two games could prove decisive.
He said: "If we go there and we are beaten by Sweden and we don't turn up against Austria and are beaten there, we are not going to get second place, are we?
"We need to go and get the points, so it will be a pivotal week for us. We will know more come Tuesday night.
"We have got to go and get the results we need and if we don't, we all know the consequences of that.
"Germany are way above most teams in the world and I think the group is theirs, so a lot of teams are fighting now for second place."
Ireland launched their campaign with a good away victory in Kazakhstan in September, and were successful on the road the following month when they returned from the Faroe Islands with three more points after a 4-1 victory.
However, what happened in between set the alarm bells ringing and came close to costing Trapattoni his job.
On October 12, Germany tore the Republic apart in Dublin, trouncing them 6-1 to illustrate the gulf in class between the sides.
Asked if Ireland are a better team away from home, Walters said with a smile: "We have had Germany at home, haven't we? Let's be honest, they are a mile ahead of a lot of teams in the world.
"You have got to pick your points up where you can. It's going to be a difficult test for us, but they are two major games we are going into and we need to get the points out of them."
Walters seems likely to start from the bench in Sweden with Shane Long favourite to partner skipper Robbie Keane.
However, the 29-year-old will be delighted simply to be on the plane after, for a few moments at least, fearing he had suffered a nasty injury in a training ground collision with the West Brom man on Tuesday.
Walters said: "I have had bad ankle injuries in the past and ruptured it, and that pain was up there above them, so I thought it was going to be worse that it was.
"But it was fine after about an hour."