Sorry don't have a solution (edit: maybe I do? see below) but following this because, now that we're on Orlando, I'll want to know soon how to link VA-created Incidents (specifically scripted ones) to their Interaction and the key to that is identifying the current Interaction... which apparently isn't as straightforward as you mention. Once I have the interaction, I presume it should just be as simple as creating a new interaction_related_record at the end of the incident-creation script.

The only thing I can think of right now is that there's no OOTB link (reference) from Conversation (sys_cs_conversation) to its respective Interaction, but I know there's the inverse of that link: a reference to the Conversation on the Interaction record - the Channel Metadata Table and Channel Metadata Record fields.

If you can get the sys_id of the current Conversation within the Conversation - I presume 'current' is the Conversation record - then you should be able to query the Interaction table and find the one Interaction record with that reference.