Hi! The name of this language will be written in is also called "Paiwan"
Is this name used in any other texts in this language?
I can see "Pinayuanan" in this book: https://www.sanmin.com.tw/product/index/002628849
Ethnologue also says "Pinayuanan": https://www.ethnologue.com/language/pwn
The Raleigh Ferrell dictionary says "pinaywanan a kai", which is very similar to "Pinayuanan" (and "kai" is language).
Perhaps it should be "Pinayuanan"? This name is supposed to be written in Paiwan, and not in English.