HELO adsf
Connection closed by foreign host.

The telnet test certainly does away with any theory that the port might be blocked. It is clearly open, and there is a listener on the other end. However, your scripts go much further than this, actually attempting to negotiate an encrypted connection, log in, and even send a message. The script is likely failing at a later stage.

At this point, I would want to test the server to see if it indeed supports TLS, the authentication information you have is correct, and that you are allowed to use it to send messages. The server might be set up to hang if it's not happy with the transaction (this is a common way to slow down spambots). Unfortunately, this behaviour may mean that you won't get much in the way of useful error messages (as you've already noticed).

I've used this guide before to test SMTP servers for access. It uses command-line tools, but you can certainly use Net::SMTP for example to achieve the same. Note that this is unlikely to be an issue particular to Perl.