The link-in and link-out nodes, when connected both maintain a list of their connections to each other in a property links. That's how/why they know about each other.
However, a link-in node does NOT get an entry for link-call nodes so does not know which link-call nodes are connected.
I am not saying the link-in nodes could not be updated to add this info but it is not operationally required and essentially that's why the link-call id is not added to the link-in node (IIRC).
As to your original question:
You can search : Search link call nodes in the editor - #4 by Steve-Mcl
