Centos – Error: XFS filesystem is not valid as a default fs type

Ultimate goal: Create an automated installation disk for CentOS, using a kickstart config file stored on an internal website.

What I've done: Created a script that

1. downloads an ISO
2. unpacks it
3. updates the isolinux.cfg file with my own menu option
4. recreates the ISO using genisoimage

All of this works, and the ISO is recreated without any errors. However, when I try to use the ISO, to start an installation, the sistem always dies at:

"new value non-existent xfs filesystem is not valid as a default fs type"
Pane is dead

Unlike this question here, my error happens pre-installation, and I'm already using lang = en_US.UTF-8. I even tried en_US, but it did not make a difference.

Lines I added to the isolinux.cfg file:

label install
  menu label ^Kickstart Installation
  menu default
  kernel vmlinuz
  append initrd=initrd.img text ramdisk=100000 lang=en_US.UTF-8 keymap=us ipv6.disable=1 ip=dhcp install inst.ks=cdrom:/kickstart.cfg

I searched online for the error, and a lot of comments seem to be related to mismatching versions for init and the kernel, or corrupted files. I am not replacing any files, and the only change I make is to the configuration file isolinux.cfg. There is no mixing of files from different versions/DVDs/images.

Has anyone had/seen the above, and have any ideas on what I should try next? I've tried playing around with the options I am putting into the file, but it doesn't seem to make a difference.

Other Info

Original image: CentOS 7.2 – DVD ISO

State of the system:

Ctrl-Alt-F1:

Ctrl-Alt-F2:

EDIT

Script that I am writing, as requested:

#!/bin/bash
#############################################################
function prepare {
    rm -rf ${ISO_EXTRACTION_DIR}
    if [ -d ${ISO_MOUNT_DIR} ]
    then
        umount ${ISO_MOUNT_DIR} 2>&1 || true
        rm -rf ${ISO_MOUNT_DIR}
    fi
    mkdir -p ${ISO_MOUNT_DIR} ${ISO_EXTRACTION_DIR}
}

function extract_iso {
    echo "Extracting ISO"

    cd $(dirname ${ISO_MOUNT_DIR})
    cp -pRf ${ISO_MOUNT_DIR}/* ${ISO_EXTRACTION_DIR}

    echo "Extracted $(ls ${ISO_EXTRACTION_DIR} | wc -l) files and directories from ISO"
}

function update_config {
    echo "Updating configuration"
    cd ${ISO_EXTRACTION_DIR}

    if [ -d "isolinux" ]
    then
        isolinux_cfg_file="${ISO_EXTRACTION_DIR}/isolinux/isolinux.cfg"
    else
        isolinux_cfg_file="${ISO_EXTRACTION_DIR}/isolinux.cfg"
    fi

    sed -i 's/timeout 600/timeout 50/' ${isolinux_cfg_file}  # Shorten timeout
    sed -i '/menu default/d' ${isolinux_cfg_file}            # Delete existing menu default
    echo "label linux" >> ${isolinux_cfg_file}
    echo "  menu default" >> ${isolinux_cfg_file}
    echo "  kernel vmlinuz" >> ${isolinux_cfg_file}
    echo "  append initrd=initrd.img text ramdisk=100000 lang=en_US.UTF-8 keymap=us ipv6.disable=1 ip=dhcp install inst.ks=cdrom:/kickstart.cfg" >> ${isolinux_cfg_file}
}

function repackage_iso {
    echo "Repackaging ISO"

    cd ${ISO_EXTRACTION_DIR}
    volume_id="${LINUX_DISTRO}-${LINUX_VERSION}-bootable"

    if [ -d "isolinux" ]
    then
        boot_cat_file="isolinux/boot.cat"
        isolinux_bin_file="isolinux/isolinux.bin"
    else
        boot_cat_file="boot.cat"
        isolinux_bin_file="isolinux.bin"
    fi

    iso_file_name="$(echo $(basename ${IMAGE_FILENAME}) | cut -d '.' -f 1)-bootable.iso"

    genisoimage \
        -U -r -v -T -J -joliet-long \
        -V 'CentOS 7 x86_64' \
        -volset "${LINUX_DISTRO}-${LINUX_VERSION}" \
        -A "${LINUX_DISTRO}-${LINUX_VERSION}" \
        -b ${isolinux_bin_file} \
        -c ${boot_cat_file} \
        -no-emul-boot \
        -boot-load-size 4 \
        -boot-info-table \
        -eltorito-alt-boot \
        -e images/efiboot.img \
        -no-emul-boot \
        -o "${IMAGE_DIR}/${iso_file_name}" .
}

prepare
check_input
mount_iso
extract_iso
unmount_iso
update_config
repackage_iso