Well you can definitely get it from a REST call to the catalog-service (.../catalog-service/api/consumer/requests/{requestID} )... and the catalog-service is exposed through the plugin, so you don't have to setup a REST host endpoint and get an Authorized bearer token to get at it.
The problem I have found in general is that the Status Details for IaaS Blueprint requests are horribly bad at presenting real value.
"requestCompletion": {
"requestCompletionState": "FAILED",
"completionDetails": "Request failed: *SERVERNAME* not found, and possibly deleted before provisioning finished."
},
I think requests are also exposed through the plugin script task classes. Let me see if I can find something.