How do I inject the new Intel RAID drivers into the restore image? Or do I have to do something different?
Drivers can be loaded during BMR via Tools > Load Driver utility from the computer drive or from a network shared folder. If you want to add them to the exising ISO just load folder inside the ISO and then use Load Drivers option in BMR. Do not fordet to Install the driver once its loaded and keep the 'Inject these drivers into operating system' option checked.
You can also create new Recovery Media with desired drivers being included during media's creation process (Include the following additional storage and network hardware drivers option) via native recovery media creation wizard: