Decoding "mtrjm" right-shift back: m (right shift typed m, but original was?) — let's reverse: If ciphertext is right-shifted, to decode, shift left: m→n? No, m left is n? Actually m left is n (as above)? No — left of m is n? That’s wrong. Let’s check row: z x c v b n m — so n is left of m, yes. So m decodes to n. t left = r, r left = e, j left = h, m left = n → "nrehn" no.
Given the complexity, I'll skip to the that makes sense:
Left of m is n? No, m is at end: left of m is n? Actually row: ... b n m — so left of m is , right of m is none. So left shift: m→n, t→r, r→e, j→h, m→n → "nrehn" — not matching.