Primary option, M-Flash and previous bios (factory or edited in another system, in one internal disk).
An external add-on USB card or you’re going to need restore factory bios, by CH341A programmer, direct SOIC8 contact, de-soldered form board or JSPI1 header… this model has no dual bios or usb bios flash back, so options are limited to programmer.
AMIBCP changes used in Aptio IV are not reflected in Aptio V bioses (Other modules like AMITSE etc… also needs changes), also we dont change the settings of a variable (most cases) we only change the visibility/access of the parent or sub-menus that are not visible, last if not visible, the string itself access.
You may try recent methods for Aptio V:
[TOOL] UEFI Editor - BIOS/UEFI Modding / BIOS Modding Guides and Problems - Win-Raid Forum (level1techs.com)