Hardcore mode, can't find roan or Pie if I dismount them

Hi, I’m doing my first hardcore playthrough. I have two quests open, At Your Service, My Lady and The Horse That Bolted. I found the roan and Pie, respectively but after riding them for awhile, I dismounted them, moved away and forgot where I left the two horses. They lack markers/icons on the map in hardcore mode and I can’t find them anymore in order to complete the quests.

Any advice?

Thanks!