Hey there! I've replayed and recorded the level in question now to refresh my memory. If you would like access to the playthrough, for now just email me at theteam@axoninteractive.ca and I'll be happy to send it along. We're working on getting the full series of levels up online for anyone else who needs help.
Meantime, the help in text form!
The elephants can definitely move! It seems there may be a bug where the prompt sometimes doesn't appear properly but just try clicking on them and pressing E or using the Z and X to tab between herds with any one of them selected and you should be able to select the elephants, and just press E on keyboard or A on controller to see where they can travel. There is exactly one hint accessible per herd so the one you are trying to reach is definitely done by the elephants.