The non-moving throttles become a non-issue as one adapts to the Bus. Yes, there is no tactile feedback as with moving throttles
WD3
I don't disagree (3000 hrs A320 family, 9000 hrs Boeing) ...BUT ... modern engines are much quiet(er) than older engines such as JT8D's. Ignoring for the moment the lack of pitch change with power on the FBW A320's, the glimpsing in your peripheral vision of thrust lever movement can be an early attention grabber and alert you to look at EPR's/N1's to see what is happening.
For someone new on type, the first thing you can be aware of is when you get a kick in the back as the beast accelerates like a scalded cat and you by then have gained 25kts or so. You are then in a recovery situation which takes some rapid actions or else a go around.
I have been caught (as I guess have most Airbus pilots) by this on occasion, typically when on a NPA using selected speed of say 160kts to 4nm, then changing to managed speed.
Now I am not suggesting that this happened in this instance, but it is one mechanism that could account for any excess speed.
As I said before, I still would put at the top of my probable causes list the slippery runway surface.