The API has no behavior when a call is answered. It is not interactive in that fashion. If use use the external_hangup when a call is live, it will hang it up. If you use it when a call is not live, it will not. That's all there is at present.
And of course Matt "could" be helpful, but on a topic like this where the question is answered, his helpfulness would be more like a quotation on hours to complete the new api module. use of the existing module is easy: there are two possibilities, test them!
As for doing it yourself or hiring someone else like us, that is a different story. For that, of course, a precise description of what you want the api to do and when would be quite useful. For instance: If you want two api functions created, one for "GET live channels" and one for "Terminate one of the channels", that would not be very difficult assuming you were supplying enough information to identify the meetme room (supplying the meetme room number, for instance, would be very good ... or the user id or ... something).