How to get same response when verifying ISO downloads

The page at

show the following messaging:

gpg: Signature made Thursday, October 17, 2019 PM03:13:47 BST

gpg: using DSA key 46181433FBB75451

gpg: Can’t check signature: No public key

gpg: Signature made Thursday, October 17, 2019 PM03:13:47 BST

gpg: using RSA key D94AA3F0EFE21092

gpg: Can’t check signature: No public key

When I first encountered the verification error, because I did not have those files, it did not give me those lines with the messaging that reported "using DSA key ...".

I reviewed the options on the man page for gpg and did not recognize any that would allow me to force that level of response.

I would like to get that detailed response, so that I could script logic to parse the message to obtain the values to trigger the response of retrieving the specified missing keys.

Anyone know how to get the desired error detail? I tried with --verbose and --debug-all options and neither of those worked for me.