In your opening post you said you have no drive installed? I have created without a problem a DOS 6.22 VM this week. But for sure with a virtual drive attached via IDE with a gigantic size of 2GB! In the past this would have been a very big drive 
Next boot with a floppy image (DOS 6.x or whatever) and use fdisk from the boot floppy to create the partition C:. Restart the VM with the floppy image still attached and the boot sequenze to the floppy drive in the BIOS of the VM and use format c: /u /s
Now the drive should boot. You need to customize config.sys and autoexec.bat if done with this approach (there are no config.sys and autoexec.bat files on the harddrive if all is done manually).