>After difficult search, I found a site that said "panch-" meant five

Yes. That was one of those vowel shifts I mentioned. When my Dad spelled "five" in Urdu, he transliterated it "panch". My Punjabi friends transliterated the word as "punj". I gave up my efforts to learn Punjabi when I learned that it has two alphabets, one of which even many native speakers have trouble mastering the use of. Given that Urdu uses the Arabic alphabet, I really should learn that instead - at least it is a more friendly language for the sinistral to write.