You asked in the correct thread and you didn't need to make a new one.
You have a question concerning something I said, and it's at the correct place.
If you want to delete a ticket manually, you will need a way to access the files.
FTPiiU everywhere is probably the easiest method.
You need Mocha CFW or Haxchi/CBHC CFW.
The tickets are located here : rights/ticket/apps
You have to know that the tickets are sometime stored in the same file, and you might want to edit that file to "cut" only the ticket you want to delete, particularly if the other ticket is not from eShop.
There's a windows program which can be used to check if a ticket file is single or multi. (I forgot the name, but I can search when I'll have more time)
Edit:
https://gbatemp.net/threads/449485/
WiiU Ticket info, it will tell you if the file is single or multi.
If it's single, you can delete it.
if it's multi, copy to PC, edit, and replace back to the console (if you delete from the console, you'll have to set the file permission manually after uploading to the console).
Guide :
I'd recommend to extract (copy) all tickets using
tik2SD homebrew.
then use
WiiU Ticket info, to read all tickets and find the titleID you need (name of the game, etc.) and determine which file you have to delete or edit.
It will also tell you if the ticket is a multi.
If it's multi, you might have to use a hexeditor to cut the ticket part you want to delete.
Then use ftpiiU to delete or replace the file.
Now connect to eShop.