We don't have datix but we have something similar and it's such a chore to complete, I wouldn't complete one if a medic made a mistake like that, I'd probably ask my manager to have a word with them when I was a staff nurse or now I'd do it myself. If we did an incident form everytime a staff member made a mistake then we'd get nothing else done, also they'd end up being escalated to higher management and they love milking it when someone fucks up, its much more helpful to just have a chat with them rather than trying to get people into trouble when it wouldn't have been intentional.
Prescribing errors I'd always incident report or patient complaints, but not something like this so there wouldn't necessarily be a paper trail.