When it comes to submitting decisions, there is always some conflict, especially when grades are on the line. The first thing we like to remind students is that there are almost no scenarios where they cannot 'make a comeback'. Depending on the severity of the error, we may just have them fix the issue going forward (such as incorrect target segments, etc).
If there is an intra-team conflict we remind the students that everything they do within the simulation software is tracked. If there is a dispute over who submitted the decisions or who made a change to a specific area, the 'Activity Log' will tell us exactly who did what, and when.