This seems unlikely to work at a Windows Command Prompt, as it needs quotes to keep going across the spaces, otherwise it assumes the space ends that value. It seems unlikely to work in the GUI because GUI doesn’t use the CLI option double-dash convention. The unquoted values go directly into the GUI input area.
Possibly the message had CLI in mind, intended to solve the CLI broken-by-spaces.
Where does fingerprint come from with SFTP (SSH)? has sample messages from so meprevious testing.
Looking at that suggests that your method is probably the easiest way to get a fingerprint back after delete:
and that probably didn’t get into any difficulty about GUI-versus-CLI-quotes, option-dashes-versus-not, etc.