Intercept "relate selected events" events action

Hi,

currently in our OBM system, we do the following:

1 select a bunch of events

2 relate them together

3 transfer control to an external ticketing system

4 get ticket nr back

5 External ID is filled in with ticket nr for the Cause event

6 An custom field (CMA) is filled in with the ticket nr for all related symptom events  

4,5,6 are handled by a Groovy script (Administration --> Connected Servers)

So far so good, works fine.

Now we have the following issue: new events come in and our operators relate them to the same Cause event (the one that had already  a External ID set) since they are the same incident.

But of course, these new events do NOT get the ticket nr set in the custom field (CMA) since this happens only initially when the Cause  + initial related events are send to the external ticketing system

So my idea would be to somehow intercept the "relate selected events" actions and trigger another Groovy script to do what I described above. So hence my question, is this feasable?

Any help definitely appreciated.