Malbim: I cannot redeem for myself, and it will be called on my name.

Rashi: I would put a blemish in my seed - "Nachalas Hashem Banim" (Tehilim 127:3). It says "Lo Yavo Amoni u'Mo'avi [bi'Khal Hashem" (Devarim 23:4). He erred about (did not expound) "Amoni", and not an Amonis. (Refer to 4:11:5:1-2 and the notes there.)

Malbim: I would ruin my inheritance; it would not be called on my name. The words also hint to blemishing his seed, like Chazal said (refer to 4:6:2:1).

Har Tzvi (EH 73 DH ul'Zeh): Indeed, I accept "Amoni", and not an Amonis. However, perhaps a later generation will rule that even Amonis is forbidden, and my descendants will be blemished.

Malbim: I refuse to redeem for two reasons - blemishing my seed, and my inheritance would not be called on my name.