The CF0: DOSDriver is configured to use fat95 by default, so if you plug in a card with FFS or such then it’ll fail with the behavior you described.
Is the CF card configured as a full disk? (i.e., with an RDB?)
If so, you might try GiggleDisk on compactflash.device to generate an appropriate mountlist.
Does it have a GUI? I remember a CU Amiga coverdisk which had something called Upper Disk Tools and I think that could do the same thing, but had a GUI, but could also browse deleted files on working partitions as well and recover them. I'd forgotten all about it until now. I'll have to check out that GiggleDisk.
