verify HTTPS 'vulnerabilities'

List,

Simple question:

I have a report from Nessus telling me that a web server is offering
'export class' cyphers for it's SSL/TLS service. Nessus also managed
to obtain an internal IP address from the host (which is correct).
Only HTTPS is open.

However the target host requires basic authentication, and I don't
have any credentials to obtain access. I would like to verify these
manually, and would usually just use something like wfetch. However,
I'm not getting the usual prompt that my encryption is too weak.
Instead in the response I can see a message saying the page cannot be
displayed. There is also no sign of the internal IP address.

Can anyone tell me how they would prove that they are not false
positives (I know the IP address is correct, but the client may want
to replicate the vulnerability so they can be sure when they go to fix
it)?

thanks

Dan