Hi and welcome 
A quick search does not turn up any support for the rocketraid 620 device. Have you done some research if it is supported on Linux? The site of the creator list no downloads for linux. This might mean that this is no hardware support for this device from the manufacturer.
When you boot the live ISO execute this in a terminal and add this to the original post so other users can see what is detected as hardware and what drivers are loaded.
inxi --admin --verbosity=7 --filter --width