Recovering a Drobo 5N

I have had the disks from my Drobo 5N sitting in protective cases for five years. We had a power cut while it was doing something and from that point I was unable to connect to it despite everything I tried. I did get in contact with a specialist Drobo recovery business who quoted over £1k to restore the files, plus I would need to need to ship it to them and would probably need some other storage…