Yup! And I only know that because redeemed 3 wells' worth just last night. (And nine more to complete that quest is currently a true story on my save file as well.)
Man, I tried my best to find the wells without looking them up, but I gave up when I had two left and used an interactive map to find them.
The most annoying part is that I still feel like they were actually in somewhat obvious places and I could've found them if I had scoured the ingame map a few more times... oh well.
For me personally, the most annoying part was realizing that I could have used the Sheikah Sensor Plus AFTER I found them all on my own. And even that was just an accident (I was trying to take a picture of a frog and the camera focused on the well instead) as I had no idea they were Hyrule Compendium entries in the first place.