Thanks for complete test. It s strange that with command line the samba Isn t listed.. Can you make a screenshot of dsm configuration (control panel. Folder. Samba) in your vm?
https://imgur.com/a/k9bKPAf
https://imgur.com/a/Ew0dWbB
https://imgur.com/a/k9bKPAf
https://imgur.com/a/Ew0dWbB