We also experienced two "bus breakdown" events. First time was to justify a 45-minute delay of our pickup time. Second time we were asked if we could allow another group who was returning from the same festival to merge because their bus with the same company had "broken down". Luckily we had the extra space and the other group was small and friendly. Looking at past reviews, it seems like they use "Sorry a bus broke down" as a common ploy to simplify their own logistics.
And another little surprise: Day of the event, we got a last minute demand to pay the entire $4000 booking in cash.