There are a few possibilities... I am assuming that this is the LAMP appliance. This info is somewhat rough guidance as TKL has matured and progressed since this appliance was released so my comments may not all be totally correct. It is best guess/vague recollection only...

TBH considering the age of this appliance (it's obviously at least 4 or 5 years old), personally I'd be looking to install the current version of TKL (v13.0) as a new VM first and migrate the data across. TKLBAM is generally the recommended way to migrate your data, although I don't know quite how it will handle going from such an old version to the latest. In fact I don't even recall if TKLBAM was available in those early TKL releases. It may be easier to just manually copy the data across...

If you go that path, then you may not need to figure this issue out.

Regardless, there are many things that could be the cause of this issue. The fact that access via other ports appears fine suggests that IP conflict is probably not the cause (although could be worth double checking anyway).

Is your intranet site working? If so then that would rule out Apache not running or global Apache config (as Apache is obviously running - phpMyAdmin uses Apache as well). It may still be phpMyAdmin specific Apache config though.

Probably one of the first places to look would be the Apache logs. You'll find them in /var/log/apache2.

Also you could do a port scan of the appliance (from another machine on your LAN) to check that it is listening on that port (as it should be).

You could also use netstat to check that the appliance is listening to port 12322 correctly.

Armed with that info you'll be in a much better position to work out your next step...