I am assuming I can only enter party line commands into this console, but is there no other way to access this command in the party line? (The IRC server I am on has disabled private messages and CTCP, and I can't telnet because I can't open ports on my school router.)
I assume you started your eggdrop using the -nt option.
If so, you are currently logged on as a virtual user with no permissions ("HQ"). You could, however, still use the .su command to switch to your owner/master account instead, and then issue the .rehash-command