Where does the rider land when they get pulled from a mount?

[Jurld]

I apologize if this has been asked/answered. I could not find the answer in the ITL Legacy Edition mounted combat rules.

We finally decided it would be "prone in the hex where the rider was sitting on their mount."

The other alternative we imagined was that it would seem more realistic if they fall to the ground beside the mount, but then we got in another "discussion" about what to do when that hex is occupied. Both figures fall to ground? The person who was pulling the rider is able to shift/step aside?

If there are RAW somewhere that we missed that covers this, please point it out, if not how do you play it in your group?