Chezzy I always use Gnome Disks to create a USB Stick
At that point I will politely bow out. My experience covers Rufus, Ventoy and Etcher and a few others but have never tried Gnome Disks to create a bootable boot image. I do know that there are lots of different ways of creating bootable ISOs that require continual updates to the software that supports using a USB as boot device.
I have used Ventoy for a number of years now and have had no issues installing many different operating systems including all versions of Solus 4.4 on various computers of widely different age and manufacture.
I politely suggest that it might be worth checking when Gnome Disks was last updated or trying a different software before condemning the Solus ISOs as faulty.