Hi Mark,
Oracle will typically need to perform some recovery work after an instance failure or in this case a shutdown abort. How long this takes is dependent on what activity in terms of DML (insert,updates, deletes) were occurring at the time the instance was aborted.
Under normal circumstances, you would not need to provision a new VDB as the Oracle databases recovery mechanisms would resolve any inconsistencies in the data and any transactions that were in a live and uncommitted state at the time of the abort would be rolled back.
The Delphix Engine should detect the instance was shut down and adjust the status of this VDB accordingly moving it to an INACTIVE state. Upon restarting it whether this be through sqlplus or through the Delphix GUI the VDB Status should return to RUNNING.
(I saw that you also created a support case for the same issue and have posted the answer here for continuity)