try boot\syslinux.cfg
It doesn't have a md5 hash so it should be fine to directly edit it without tripping on the electric fence.

PROMPT 0
TIMEOUT 50
DEFAULT /boot/vesamenu.c32
#TOTALTIMEOUT 450
#MENU BACKGROUND /boot/splash.png
MENU TITLE Architecture selection
INCLUDE /boot/colors.cfg
MENU TABMSG Press [F1] to get Help, press [Tab] to edit options.

F1 /boot/verh1.txt

INCLUDE kernels.cfg