The camping grounds adventurer search function does not work with names including an '_' character.
(1) Find a player with an underscore in their name, for example my guildmate Ori_Coren.
(2) Search their name in the adventurer search, found under Camping Grounds on this website.
(3) Wait for the page to load and the adventurer will not appear.
I have attempted to reproduce this while logged in, logged out, copy and pasted the adventurer's name dircetly from the guild page, and guided a guildmate to reproduce this.
Reproducable 100%