That’s not pinyin nor Wade Giles.
Yes, it’s a mishmash. I learned Bau Pau Mau in Taiwan, if you know what that is. It is an exact phonetic, more precise than either Wade Giles or Pinyin. There was another system created by the great Lin Yutang but never caught on. It had to do with doubling vowels according to tone. What is your knowledge of Chinese?