I am fairly sure they are still using Sabre Sonic. Probably with a million patches.
The chances of VA doing any major change to Amadeus or even New Skies is practically zero, cost is one thing, however they likely lack internal IT capability to even take on such a change, and the big elephant in the room, the risk of a changeover going pear shaped.
VA and Velocity’s software are just trash. I would probably take a longer term view and perhaps plan an upgrade say 10 years away, get the ball rolling now. I think even New Skies would be a step forward compared to what they have now, pretty basic but VA is just a basic airline at the end of the day.