Cannot boot openSUSE NET iso from hard disk

I followed this
https://forums.opensuse.org/showthread.php/484223-How-to-boot-a-openSUSE-DVD-from-hard-disk-with-Grub2

For the openSUSE DVD iso it still works out of the box, but for the NET iso: after the green bars loading basic drivers, hardware, etc, instead of getting to Yast GUI installer, I get to a text mode interface with this message:

Please make sure your installation medium is available

Choose the URL to retry

hd:/isos/opensuse-Leap...].iso
http://download.opensuse.org/distribution/leap/15.4/repo/oss/
Enter another URL

If choosing the second option it works -though it takes time for it to download and proceed-, but I expected the same behavior as with the DVD iso.
Choosing first option just gets back to this same message.
Both isos have the exact grub.cfg.

Could someone perhaps help, please?
Thanks beforehand.

NET ISO by definition does not contain installation image and loads everything from network.