I've had this happen to me as well, same type of key and van. I was at a pick-up about 40 min from the station and had 4 deliveries left. Had about 90 min to get the van with outbound back to the station too, but I made it after he brought me a key.
I've also had an Isuzu Reach wristband/fob get wet on my break when I was washing my hands and the fob wouldn't work until it had dried out overnight. Luckily that time I was a lot closer to the station for someone to run me out a spare wristband.