I can not answer your question, however she can recieve the AHV payment abroad.
"The beneficiary of the AHV can choose his/her payment address freely (transfer to Switzerland or abroad). The AHV benefits for people living abroad are generally paid out in the local currency of their payment address."
"Exception for recipients of a survivor's pension: If you are a citizen of a country with which Switzerland has not concluded a social security agreement, but the deceased was Swiss national or was a citizen of a country with which Switzerland has concluded a social security agreement, you are still entitled to your benefit abroad."
https://www.zas.admin.ch/zas/de/home...-etranger.html