Welcome to the club,
I have the same model. Don't think it's the same problem, exactly, but when I got mine, about nine months ago, I found that it was easy to stall when pulling away at junctions or roundabouts. I no longer have that problem as I now give it a bit more ‚Äúwelly‚ÄĚ and that seems to work. It is very much like having to relearn clutch and accelerator control when moving off.
Is it only your wife who has the problem? If so, it could be that she drives a lot more gently than you , when pulling away.
Give it a try -- perhaps with her in the car -- before shelling out to fix something that might not be there.
Let me know if this helps,