add new "link type" to relate existing ticket to Request Task

Is it possible to leverage on oob related record "link type" method to related "Change ticket" with "Request task ticket" by add new relation? 

The following is what we found/did to try  : 

1. Add a new relationship type named "Caused by Request Task"

2. Check the oob Change workflow (normal) "Associate Record" object is calling ruleset name "Associate Record" , which will trigger javascript RelationUtil.populateAction( vars.$recordType, "assoc");

3. Locate the RelationUtil script library and function populationAction , found it will required a new "securityActionMap" , which will make the script return a new action "assocrmtask"

4. Locate application: us.screlate.options | label : check.action, via db-application, add new action assoc.rmtask | assocrmtask

5. Add new us.screlate.options application record with label "assoc.rmtask" 

But, the test result is, when we select this new relation type, click "Link Existing Record" button, the "request task ticket  pop up form" did not prompt as expected.

We expect it shall prompt a "pop up form" which allow us to key in the request task ticket number, like how it should prompt for incident/change/etc ticket. below. 

So, we would like to know , did we explore on a wrong direction OR  something we did not do right/missing OR it just simply not doable (cannot leverage on this oob approach)?