How his friends would do this can be stated clearly. Alternate translation: "claim that my humiliation is proof against me" or "use my humiliation as evidence that I am guilty" (See: [[rc://en/ta/man/translate/figs-explicit]])
The abstract noun "humiliation" can be expressed with the verb "humiliate." Alternate translation: "claim that what has happened to humiliate me proves that I am guilty" (See: [[rc://en/ta/man/translate/figs-abstractnouns]])