I think third puzzle in 5.3 has multiple solutions.
↓rot13
Gur ehyrf V thrffrq ner: “Rknpgyl gjb funqrq pryyf unir rknpgyl gjb funqrq pryyf gb gurve yrsg” (zrnavat “Gurer ner rknpgyl gjb ebjf pbagnvavat guerr be zber funqrq pryyf”) naq “Nyy funqrq pryyf ner begubtbanyyl nqwnprag gb gjb bgure funqrq pryyf.”
Ohg vs lbh funqr gur gbc-yrsg 2×2 oybpx naq gura rkgraq gur ertvba va n evat fb gung vg cnffrf guebhtu gur nyernql funqrq pryyf, vg fgvyy fngvfsvrf gur ehyrf. Naq va gung fgngr, lbh pna nqqvgvbanyyl funqr gur obggbz-yrsg 2×2 oybpx, naq vg fgvyy fngvfsvrf gur ehyrf