render order/ multipass shaders (hidden surface shader path)

Is it possible to render one material / shader with two passes in different Queues?

I have a character surface shader and a pass for rendering the character with special color behind objects (zfail). It is important that for multipart characters all special passes of all character (parts) are rendered first and then all surface shader passes of all character (parts).

I gave the pass a different Queue Tag but this changed nothing:

 Shader
 {
   Subshader
   {
     Pass
     {
       // hidden surface pass
       Tags { "Queue"="Transparent-2" }
       // ..
     }
 
     // main rendering surface shader
     Tags { "Queue"="Transparent-1" }
     // ..
   }
 }

Am I doing something wrong? Is it possibly what I want or do I need to solve that with custom scripting (and painting)?