I think isn't possible, because, according to online help, there isn't any password parameter in the connection pseudo-url
When connecting to QlikView Server from Windows clients, either via the Open in Server dialog or via link files, a pseudo-URL is used as document address.
The syntax is:
username is a Windows user ID. The parameter is optional.
hostname is the name of the host. The parameter is obligatory.
documentname is the name of the QlikView document (excluding qvw extension). The parameter is optional.
port (e.g. 4749) can be used for specifying a specific port used by the server
protocol (e.g. http) can be used for specifying a tunneling protocol. The parameter is optional.
@ without username denotes anonymous identity.
If user identity is omitted altogether, the logged in Windows identity is assumed.
Can you use OpenDocEx?
I use it to pass in username and password when I want to open a QV doc without my user seeing the prompt. That said, I have only dealt with QV desktop, as my app is a desktop only app, and it embeds QV that function as a desktop only version (interaction is done via the OCX interface).