I was having the same issue with a 9305-16i, when csm is enabled (had to connect a dedicated gfx card) igpu gets disabled.
Had to remove the bios from HBA using "lsiutil" I followed the instructions from this video.
It has been a while but I found it originally documented.
Edit the docker and where you have your storage set to, click edit and it will probably be currently be set to read only, change that and you should be able to now restore files. (I have mine set to read/write slave) there may be a better setting but still relatively new to this.