That is an abscess, and needs to be lanced. Normally you wait until it is 'ripe,' then lance it to get out all the pus. It is thought that ear abscesses occur because of an infection someplace in the body, not necessarily in the ear. It would be a very good idea to take this tortoise to a vet for testing.
Omg, I had all the equipment ready, will ask my friend's missus to do it if she agree. She's a surgeon but not vet surgeon, dunno will she do it or not, but definitely would be better than I'm the one doing it