Are one time pads still secure when using randomly generated words as the pad?
Do those look like English words to you?

WHTVI AUCFU RETFK OMSAL
MYMNE ZIEGP UKVTF WZHOK


(Quoted from the page.)

When they say ‘5-letter words’, they don't mean words chosen from an English dictionary.  They mean that they rolled a d26 five times independently and strung the resulting letters together, with spaces between every five letters and line breaks between every four ‘words’ for legibility.  This method is just as secure as using a d2 (i.e., flipping a coin) to choose the bits of a binary one-time pad; it just uses a different alphabet.